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There is great promise in breast cancer risk stratification to target screening and prevention. It is unclear whether adding gene panels to other risk tools improves breast cancer risk stratification and adds discriminatory benefit on a population basis.In total, 10,025 of 57,902 women aged 46 to 73 years in the Predicting Risk of Cancer at Screening study provided DNA samples. A case-control study was used to evaluate breast cancer risk assessment using polygenic risk scores (PRSs), cancer gene panel (n = 33), mammographic density (density residual [DR]), and risk factors collected using a self-completed 2-page questionnaire (Tyrer-Cuzick [TC] model version 8). In total, 525 cases and 1410 controls underwent gene panel testing and PRS calculation (18, 143, and/or 313 single-nucleotide polymorphisms [SNPs]).Actionable pathogenic variants (PGVs) in BRCA1/2 were found in 1.7% of cases and 0.55% of controls, and overall PGVs were found in 6.1% of cases and 1.3% of controls. A combined assessment of TC8-DR-SNP313 and gene panel provided the best risk stratification with 26.1% of controls and 9.7% of cases identified at1.4% 10-year risk and 9.01% of controls and 23.3% of cases at ≥8% 10-year risk. Because actionable PGVs were uncommon, discrimination was identical with/without gene panel (with/without: area under the curve = 0.67, 95% CI = 0.64-0.70). Only 7 of 17 PGVs in cases resulted in actionable risk category change. Extended case (n = 644)-control (n = 1779) series with TC8-DR-SNP143 identified 18.9% of controls and only 6.4% of stage 2+ cases at1.4% 10-year risk and 20.7% of controls and 47.9% of stage 2+ cases at ≥5% 10-year risk.Further studies and economic analysis will determine whether adding panels to PRS is a cost-effective strategy for risk stratification.

PurposeTo investigate frequency of germline pathogenic variants (PVs) in women with ductal carcinoma in situ (DCIS) and grade 1 invasive breast cancer (G1BC).MethodsWe undertookBRCA1/2analysis in 311 women with DCIS and 392 with G1BC and extended panel testing (non-BRCA1/2) in 176/311 with DCIS and 156/392 with G1BC. We investigated PV detection by age at diagnosis, Manchester Score (MS), DCIS grade and receptor status.Results30/311 (9.6%) with DCIS and 16/392 with G1BC (4.1%) had aBRCA1/2PV (p=0.003), and 24/176-(13.6%) and 7/156-(4.5%), respectively, a non-BRCA1/2PV (p=0.004). Increasing MS was associated with increased likelihood ofBRCA1/2PV in both DCIS and G1BC, although the 10% threshold was not predictive for G1GB. 13/32 (40.6%) DCIS and 0/17 with G1BC BRCA1/2) and 9/90 (non-BRCA1/2), and 8/47 (BRCA1/2) and 8/45 (non-BRCA1/2), respectively. 6/9BRCA1and 3/26BRCA2-associated DCIS were oestrogen receptor negative-(p=0.003). G1BC population testing showed no increased PV rate (OR=1.16, 95% CI 0.28 to 4.80).ConclusionDCIS is more likely to be associated with bothBRCA1/2and non-BRCA1/2PVs than G1BC. Extended panel testing ought to be offered in young-onset DCIS where PV detection rates are highest.

Polygenic risk scores (PRS) for disease risk stratification show great promise for application in general populations, but most are based on data from individuals of white European origin. We assessed two well validated PRS (SNP18, SNP143) in the Predicting-Risk-of-Cancer-At-Screening (PROCAS) study in North-West England for breast cancer prediction based on ethnicity. Overall, 9475 women without breast cancer at study entry, including 645 who subsequently developed invasive breast cancer or ductal carcinoma in situ provided DNA. All were genotyped for SNP18 and a subset of 1868 controls were genotyped for SNP143. For white Europeans both PRS discriminated well between individuals with and without cancer. For n=395 Black (n=112), Asian (n=119), mixed (n=44) or Jewish (n=120) women without cancer both PRS overestimated breast cancer risk, being most marked for women of Black and Jewish origin (p

PURPOSE To investigate the contribution of PALB2 pathogenic gene variants (PGVs, PALB2_PGV) and the CHEK2 c.1100delC (CHEK2_1100delC) PGV to familial breast and ovarian cancer, and PALB2_PGV associated breast cancer pathology. METHODS Outcomes of germline PALB2_PGV and CHEK2_1100delC testing were recorded in 3,127 women with histologically confirmed diagnoses of invasive breast cancer, carcinoma in situ, or epithelial nonmucinous ovarian cancer, and 1,567 female controls. Breast cancer pathology was recorded in PALB2_PGV cases from extended families. RESULTS Thirty-five PALB2 and 44 CHEK2_1100delC PGVs were detected in patients (odds ratio [OR] PALB2 breast-ovarian = 5.90 [95% CI: 1.92-18.36], CHEK2 breast-ovarian = 4.46 [95% CI: 1.86-10.46], PALB2 breast = 6.16 [95% CI: 1.98-19.21], CHEK2 breast = 4.89 [95% CI: 2.01-11.34]). Grade 3 ER-positive HER2-negative, grade 3 and triple negative (TN) tumors were enriched in cases with PALB2 PGVs compared with all breast cancers known to our service (respectively: 15/43, 254/1,843, P = 0.0005; 28/37, 562/1,381, P = 0.0001; 12/43, 204/1,639, P

BackgroundWhile the likelihood of identifying constitutional breast cancer-associated BRCA1, BRCA2 and TP53 pathogenic variants (PVs) increases with earlier diagnosis age, little is known about the correlation with age at diagnosis in other predisposition genes. Here, we assessed the contribution of known breast cancer-associated genes to very early onset disease.MethodsSequencing of BRCA1, BRCA2, TP53 and CHEK2 c.1100delC was undertaken in women with breast cancer diagnosed ≤30 years. Those testing negative were screened for PVs in a minimum of eight additional breast cancer-associated genes. Rates of PVs were compared with cases ≤30 years from the Prospective study of Outcomes in Sporadic vs Hereditary breast cancer (POSH) study.ResultsTesting 379 women with breast cancer aged ≤30 years identified 75 PVs (19.7%) in BRCA1, 35 (9.2%) in BRCA2, 22 (5.8%) in TP53 and 2 (0.5%) CHEK2 c.1100delC. Extended screening of 184 PV negative women only identified eight additional actionable PVs. BRCA1/2 PVs were more common in women aged 26–30 years than in younger women (p=0.0083) although the younger age group had rates more similar to those in the POSH cohort. Out of 26 women with ductal carcinoma in situ (DCIS) alone, most were high-grade and 11/26 (42.3%) had a PV (TP53=6, BRCA2=2, BRCA1=2, PALB2=1). This PV yield is similar to the 61 (48.8%) BRCA1/2 PVs identified in 125 women with triple-negative breast cancer. The POSH cohort specifically excluded pure DCIS which may explain lower TP53 PV rates in this group (1.7%).ConclusionThe rates of BRCA1, BRCA2 and TP53 PVs are high in very early onset breast cancer, with limited benefit from testing of additional breast cancer-associated genes.

Genome-wide analysis identifies 32 loci associated with breast cancer susceptibility, accounting for estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 status and tumor grade. Breast cancer susceptibility variants frequently show heterogeneity in associations by tumor subtype(1-3). To identify novel loci, we performed a genome-wide association study including 133,384 breast cancer cases and 113,789 controls, plus 18,908 BRCA1 mutation carriers (9,414 with breast cancer) of European ancestry, using both standard and novel methodologies that account for underlying tumor heterogeneity by estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 status and tumor grade. We identified 32 novel susceptibility loci (P < 5.0 x 10(-8)), 15 of which showed evidence for associations with at least one tumor feature (false discovery rate < 0.05). Five loci showed associations (P < 0.05) in opposite directions between luminal and non-luminal subtypes. In silico analyses showed that these five loci contained cell-specific enhancers that differed between normal luminal and basal mammary cells. The genetic correlations between five intrinsic-like subtypes ranged from 0.35 to 0.80. The proportion of genome-wide chip heritability explained by all known susceptibility loci was 54.2% for luminal A-like disease and 37.6% for triple-negative disease. The odds ratios of polygenic risk scores, which included 330 variants, for the highest 1% of quantiles compared with middle quantiles were 5.63 and 3.02 for luminal A-like and triple-negative disease, respectively. These findings provide an improved understanding of genetic predisposition to breast cancer subtypes and will inform the development of subtype-specific polygenic risk scores.

Purpose: Lobular breast cancer (LBC) accounts for ~ 15% of breast cancer. Here, we studied the frequency of pathogenic germline variants (PGVs) in an extended panel of genes in women affected with LBC. Methods: 302 women with LBC and 1567 without breast cancer were tested for BRCA1/2 PGVs. A subset of 134 LBC affected women who tested negative for BRCA1/2 PGVs underwent extended screening, including: ATM, CDH1, CHEK2, NBN, PALB2, PTEN, RAD50, RAD51D, and TP53.Results: 35 PGVs were identified in the group with LBC, of which 22 were in BRCA1/2. Ten actionable PGVs were identified in additional genes (ATM(4), CDH1(1), CHEK2(1), PALB2(2) and TP53(2)). Overall, PGVs in three genes conferred a significant increased risk for LBC. Odds ratios (ORs) were: BRCA1: OR = 13.17 (95%CI 2.83–66.38; P = 0.0017), BRCA2: OR = 10.33 (95%CI 4.58–23.95; P ATM: OR = 8.01 (95%CI 2.52–29.92; P = 0.0053). We did not detect an increased risk of LBC for PALB2, CDH1 or CHEK2. Conclusion: The overall PGV detection rate was 11.59%, with similar rates of BRCA1/2 (7.28%) PGVs as for other actionable PGVs (7.46%), indicating a benefit for extended panel genetic testing in LBC. We also report a previously unrecognised association of pathogenic variants in ATM with LBC.

In families with multiple affected individuals with early-onset breast/ovarian cancer pathogenic variants in BRCA1 or BRCA2 are identified in approximately 20% of the cases. Extensive efforts have been made to identify additional highly penetrant breast cancer genes or alternative mutational mechanisms affecting BRCA1 and BRCA2 to explain the missing heritability. It has been proposed that part of the missing heritability may be explained by gene silencing due to promoter methylation of cancer associated genes, as described in colorectal cancer (MLH1 and MSH2). Here, for the first time, we report two independent families with multiple individuals affected by breast and ovarian cancer with transgenerational promoter methylation of BRCA1. RNA analysis of BRCA1 in the germline of breast/ovarian families, previously found to be BRCA1/2 mutation negative by Sanger sequencing and copy number analysis, identified two families with allelic loss of expression. To investigate the mechanism of transcriptional silencing, a total of 14 affected and unaffected family members from these two families were tested for BRCA1 promoter methylation by pyrosequencing in blood, buccal, and hair follicle cells. Allele specific methylation was determined by clonal bisulphite sequencing. BRCA1 promoter methylation in all three germ layers was present in 11 of 14 family members. Of the 7 women with promoter methylation five were affected with grade 3 breast/high grade serous ovarian cancer. The four males with BRCA1 promoter methylation had no history of cancer. Methylation levels were ˜50%, consistent with the silencing of one allele detected in RNA in these family members. Clonal bisulphite sequencing of an affected family member of each family confirmed that the alternative allele was specifically methylated. Interestingly, in both families the methylation pattern of the BRCA1 promoter segregated with the same novel heterozygous variant in the 5'UTR of BRCA1. These results indicate a novel mechanism for familial breast/ovarian cancer, caused by epigenetic silencing of one allele by transgenerational hypermethylation of the BRCA1 promoter, secondary to a variant in cis of BRCA1. We propose that methylation analyses are indicated in all families affected by early onset breast/ovarian cancer where standard mutation screening of BRCA1/2 has not identified a causative variant. Citation Format: van Veen EM, Smith MJ, Byers HJ, Wallace AJ, Lalloo FI, Newman WG, Evans DGR. Transgenerational epigenetic silencing of BRCA1 due to a germline variant unmasks a new mechanism for familial breast and ovarian cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD1-05.

Breast cancer susceptibility variants frequently show heterogeneity in associations by tumor subtype. To identify novel loci, we performed a genome-wide association study (GWAS) including 133,384 breast cancer cases and 113,789 controls, plus 18,908 BRCA1 mutation carriers (9,414 with breast cancer) of European ancestry, using both standard and novel methodologies that account for underlying tumor heterogeneity by estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status and tumor grade. We identified 32 novel susceptibility loci (P-8), 15 of which showed evidence for associations with at least one tumor feature (false discovery rate PIn-silico analyses showed these five loci contained cell-specific enhancers that differed between normal luminal and basal mammary cells. The genetic correlations between five intrinsic-like subtypes ranged from 0.35 to 0.80. The proportion of genome-wide chip heritability explained by all known susceptibility loci was 37.6% for triple-negative and 54.2% for luminal A-like disease. These findings provide an improved understanding of genetic predisposition to breast cancer subtypes and will inform the development of subtype-specific polygenic risk scores.

Breast cancer susceptibility variants frequently show heterogeneity in associations by tumor subtype1–3. To identify novel loci, we performed a genome-wide association study (GWAS) including 133,384 breast cancer cases and 113,789 controls, plus 18,908 BRCA1 mutation carriers (9,414 with breast cancer) of European ancestry, using both standard and novel methodologies that account for underlying tumor heterogeneity by estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status and tumor grade. We identified 32 novel susceptibility loci (P < 5.0 × 10−8), 15 of which showed evidence for associations with at least one tumor feature (false discovery rate (FDR)

Purpose To improve breast cancer risk stratification to enable more targeted early detection/prevention strategies that will better balance risks and benefits of population screening programmes. Methods 9362 of 57,902 women in the Predicting-Risk-Of-Cancer-At-Screening (PROCAS) study who were unaffected by breast cancer at study entry and provided DNA for a polygenic risk score (PRS). The PRS was analysed alongside mammographic density (density-residual-DR) and standard risk factors (Tyrer-Cuzick-model) to assess future risk of breast cancer based on tumour stage receptor expression and pathology. Results 195 prospective incident breast cancers had a prediction based on TC/DR/PRS which was informative for subsequent breast cancer overall [IQ-OR 2.25 (95% CI 1.89–2.68)] with excellent calibration-(0.99). The model performed particularly well in predicting higher stage stage 2+ IQ-OR 2.69 (95% CI 2.02–3.60) and ER + BCs (IQ-OR 2.36 (95% CI 1.93–2.89)). DR was most predictive for HER2+ and stage 2+ cancers but did not discriminate as well between poor and extremely good prognosis BC as either Tyrer-Cuzick or PRS. In contrast, PRS gave the highest OR for incident stage 2+ cancers, [IQR-OR 1.79 (95% CI 1.30–2.46)]. Conclusions A combined approach using Tyrer-Cuzick/DR/PRS provides accurate risk stratification, particularly for poor prognosis cancers. This provides support for reducing the screening interval in high-risk women and increasing the screening interval in low-risk women defined by this model. Electronic supplementary material The online version of this article (10.1007/s10549-019-05210-2) contains supplementary material, which is available to authorized users.

Panels of single nucleotide polymorphisms (SNPs) stratify risk for breast cancer in women from the general population, but studies are needed assess their use in a fully comprehensive model including classical risk factors, mammographic density and more than 100 SNPs associated with breast cancer. A case–control study was designed (1,668 controls, 405 cases) in women aged 47–73 years attending routine screening in Manchester UK, and enrolled in a wider study to assess methods for risk assessment. Risk from classical questionnaire risk factors was assessed using the Tyrer–Cuzick model; mean percentage visual mammographic density was scored by two independent readers. DNA extracted from saliva was genotyped at selected SNPs using the OncoArray. A predefined polygenic risk score based on 143 SNPs was calculated (SNP143). The odds ratio (OR, and 95% confidence interval, CI) per interquartile range (IQ‐OR) of SNP143 was estimated unadjusted and adjusted for Tyrer–Cuzick and breast density. Secondary analysis assessed risk by oestrogen receptor (ER) status. The primary polygenic risk score was well calibrated (O/E OR 1.10, 95% CI 0.86–1.34) and accuracy was retained after adjustment for Tyrer–Cuzick risk and mammographic density (IQ‐OR unadjusted 2.12, 95% CI% 1.75–2.42; adjusted 2.06, 95% CI 1.75–2.42). SNP143 was a risk factor for ER+ and ER− breast cancer (adjusted IQ‐OR, ER+ 2.11, 95% CI 1.78–2.51; ER− 1.81, 95% CI 1.16–2.84). In conclusion, polygenic risk scores based on a large number of SNPs improve risk stratification in combination with classical risk factors and mammographic density, and SNP143 was similarly predictive for ER‐positive and ER‐negative disease., What's new? Panels of single nucleotide polymorphisms (SNPs) stratify risk for breast cancer in women from the general population, but studies are needed to assess their use in a fully‐comprehensive model including classical questionnaire risk factors, mammographic density, and more than 100 SNPs associated with breast cancer. In this study, the predictive ability of a predefined panel of 143 SNPs was assessed after adjustment for questionnaire risk factors and mammography density using women from a U.K. cohort. The panel showed substantial improvement in risk stratification in combination with classical risk factors and mammographic density, for both oestrogen receptor‐positive and negative breast cancer.

PURPOSE: Genetic variation may influence women's response to ovarian stimulation therapy. The purpose of this study was to investigate any effects of genetic variants in the anti-Müllerian hormone (AMH) and AMH type II receptor genes on ovarian response/treatment outcomes and on current markers of ovarian reserve in individuals undergoing in vitro fertilisation (IVF) treatment.METHODS: In this prospective observational study, we genotyped the AMH c.146G>T, p.(Ile49Ser) and AMHR2 -482A>G variants in 603 unrelated women undergoing their first cycle of controlled ovarian stimulation for IVF and ICSI (intracytoplasmic sperm injection) using gonadotrophins at a tertiary referral centre for reproductive medicine. Pelvic ultrasound and blood hormone levels were taken on days 2-3 of the cycle. Genotypes were determined using TaqMan allelic discrimination assay. Regression analysis was performed to assess the relationship between the genotypes and the ovarian reserve markers (FSH, AMH, antral follicle count) and the early outcomes of response (number of oocytes retrieved and gonadotropin dose) as well as the treatment outcome (live birth).RESULTS: There were no significant associations between the variants AMH c.146G>T and AMHR2 -482A>G with ovarian response in terms of number of oocytes retrieved (p = 0.08 and p = 0.64, respectively), live births (p = 0.28 and p = 0.52) and/or markers of ovarian reserve.CONCLUSIONS: Genotyping of the AMH c.146G>T and AMHR2 -482A>G polymorphisms does not provide additional useful information as a predictor of ovarian reserve or ovarian response and treatment outcomes.

Heterozygous whole gene deletions (WGDs), and intragenic microdeletions, account for a significant proportion of mutations underlying cancer predisposition syndromes. We analyzed the frequency and genotype-phenotype correlations of microdeletions in 12 genes (BRCA1, BRCA2, TP53, MSH2, MLH1, MSH6, PMS2, NF1, NF2, APC, PTCH1, and VHL) representing seven tumor predisposition syndromes in 5,897 individuals (2,611 families) from our center. Overall, microdeletions accounted for 14% of identified mutations. As expected, smaller deletions or duplications were more common (12%) than WGDs (2.2%). Where a WGD was identified in the germline in NF2, the mechanism of somatic second hit was not deletion, as previously described for NF1. For neurofibromatosis type 1 and 2, we compared the mechanism of germline deletion. Unlike NF1, where three specific deletion sizes account for most germline WGDs, NF2 deletion breakpoints were different across seven samples tested. One of these deletions was 3.93 Mb and conferred a severe phenotype, thus refining the region for a potential NF2 modifier gene to a 2.04-Mb region on chromosome 22. The milder phenotype of NF2 WGDs may be due to the apparent absence of chromosome 22 loss as the second hit. These observations of WGD phenotypes will be helpful for interpreting incidental findings from microarray analysis and next-generation sequencing.

BackgroundPathogenic variants in BRCA1 or BRCA2 are identified in ~20% of families with multiple individuals with early-onset breast/ovarian cancer. Extensive searches for additional highly penetrant genes or alternative mutational mechanisms altering BRCA1/2 have not explained the missing heritability. For the first time, we report transgenerational epigenetic silencing of BRCA1 due to promoter hypermethylation in two families with breast/ovarian cancer.MethodsBRCA1 promoter methylation of ten CpG dinucleotides in breast/ovarian cancer families without germline BRCA1/2 pathogenic variants was assessed by pyrosequencing and clonal bisulfite sequencing. RNA and DNA sequencing of BRCA1 from lymphocytes was undertaken to establish allelic expression and the presence of germline variants.FindingsBRCA1 promoter hypermethylation was identified in two of 49 families with multiple women affected with grade 3 breast/high grade serous ovarian cancer. Soma-wide BRCA1 promoter hypermethylation was confirmed in blood, buccal mucosa and hair follicles. Methylation levels were ~50%, consistent with the silencing of one allele and confirmed by clonal bisulfite sequencing. RNA sequencing revealed allelic loss of BRCA1 expression in both families and this segregated with a novel heterozygous variant c.-107A>T in the BRCA1 5’UTR.InterpretationOur results indicate a novel mechanism for familial breast/ovarian cancer, caused by epigenetic silencing of the BRCA1 promoter, segregating with an in cis 5’UTR variant in two independent families. We propose that methylation analyses are indicated in all families affected by early onset breast/ovarian cancer without a BRCA1/2 pathogenic variant.FundingFunded by Prevent Breast Cancer (GA 12-006 and GA 15-002) and the Manchester NIHR Biomedical Research Centre (IS-BRC-1215-20007).

The megalencephaly capillary malformation syndrome (MCAP, OMIM 602501) is known to be associated with mosaic mutations in PIK3CA occurring during embryogenesis. Standard sequencing technologies are relatively poor at indentifying sequence changes that only affect a small percentage of cells, and the mutations are frequently not identified in lymphocyte DNA, with biopsies of the affected tissues often being required to detect mosaic mutations. Such invasive procedures are not always acceptable to parents. We describe the case of a patient in whom we were able to confirm a causative PIK3CA mutation, first found thorugh next-generation sequencing, in several tissue types including a secondary tooth. As part of this work, we were also able to begin validating dental tissue for potential use in genetic testing, as we achieved excellent DNA yields with minimal effort, even from deciduous teeth shed some years earlier.

Gorlin syndrome is an autosomal dominant disorder characterized by multiple early-onset basal cell carcinoma, odontogenic keratocysts and skeletal abnormalities. It is caused by heterozygous mutations in the tumour suppressor PTCH1. Routine clinical genetic testing, by Sanger sequencing and multiplex ligation-dependent probe amplification (MLPA) to confirm a clinical diagnosis of Gorlin syndrome, identifies a mutation in 60–90 % of cases. We undertook RNA analysis on lymphocytes from ten individuals diagnosed with Gorlin syndrome, but without known PTCH1 mutations by exonic sequencing or MLPA. Two altered PTCH1 transcripts were identified. Genomic DNA sequence analysis identified an intron 7 mutation c.1068-10T>A, which created a strong cryptic splice acceptor site, leading to an intronic insertion of eight bases; this is predicted to create a frameshift p.(His358Alafs*12). Secondly, a deep intronic mutation c.2561-2057A>G caused an inframe insertion of 78 intronic bases in the cDNA transcript, leading to a premature stop codon p.(Gly854fs*3). The mutations are predicted to cause loss of function of PTCH1, consistent with its tumour suppressor function. The findings indicate the importance of RNA analysis to detect intronic mutations in PTCH1 not identified by routine screening techniques.

Spontaneous ovarian hyperstimulation syndrome is an extremely rare condition that occurs in the absence of ovarian hyperstimulation treatment. It can lead to significant morbidity and mortality, and therefore early diagnosis and supportive treatment are essential. We report an affected mother and her daughter with a previously reported heterozygous activating mutation in the FSHR gene. We performed a literature review with particular regard to pathogenesis, with a view to suggesting a pathophysiological classification system and a diagnostic algorithm to assist in the management of this rare condition.

The deficiency of ubiquitously expressed glucose-6-phosphatase (G6PC3) enzyme is known to result in a syndrome characterized by severe congenital neutropenia, prominent superficial venous pattern, congenital heart defects and genito-urinary malformations. Here, we describe four patients from three families with non-syndromic severe congenital neutropenia and identify four G6PC3 mutations as causative in these cases. Thus we demonstrate that G6PC3 mutations also result in a non-syndromic form of severe congenital neutropenia. We propose that G6PC3 deficiency should be considered as part of the differential diagnoses in any patient with unexplained congenital neutropenia. Additionally, we show a relationship between the genotype and non-hematological phenotype of G6PC3 deficiency. These findings may provide an insight into the role of the G6PC3 enzyme and glucose metabolism in developmental pathways.

BRCA1 and BRCA2 are major breast cancer susceptibility genes. Nineteen single nucleotide polymorphisms (SNPs) at 18 loci have been associated with breast cancer. We aimed to determine whether these predict breast cancer incidence in women with BRCA1/BRCA2 mutations. BRCA1/2 mutation carriers identified through the Manchester genetics centre between 1996 and 2011 were included. Using published odds ratios (OR) and risk allele frequencies, we calculated an overall breast cancer risk SNP score (OBRS) for each woman. The relationship between OBRS and age at breast cancer onset was investigated using the Cox proportional hazards model, and predictive ability assessed using Harrell's C concordance statistic. In BRCA1 mutation carriers we found no association between OBRS and age at breast cancer onset: OR for the lowest risk quintile compared to the highest was 1.20 (95% CI 0.82–1.75, Harrell's C = 0.54), but in BRCA2 mutation carriers the association was significant (OR for the lowest risk quintile relative to the highest was 0.47 (95% CI 0.33–0.69, Harrell's C = 0.59). The 18 validated breast cancer SNPs differentiate breast cancer risks between women with BRCA2 mutations, but not BRCA1. It may now be appropriate to use these SNPs to help women with BRCA2 mutations make maximally informed decisions about management options.

A case–control study from two randomised breast cancer prevention trials of tamoxifen and raloxifene (P-1 and P-2) identified single-nucleotide polymorphisms (SNPs) in or near genes ZNF423 and CTSO as factors which predict which women will derive most anti-cancer benefit from selective oestrogen receptor modulator (SERM) therapy. In this article, we further examine this question using blood samples from two randomised tamoxifen prevention trials: the International Breast Cancer Intervention Study I (IBIS-I) and the Royal Marsden trial (Marsden). A nested case–control study was designed with 2:1 matching in IBIS-I and 1:1 matching in Marsden. The OncoArray was used for genotyping and included two SNPs previously identified (rs8060157 in ZNF423 and rs10030044 near CTSO), and 102 further SNPs within the same regions. Overall, there were 369 cases and 662 controls, with 148 cases and 268 controls from the tamoxifen arms. Odds ratios were estimated by conditional logistic regression, with Wald 95 % confidence intervals. In the tamoxifen arms, the per-allele odds ratio for rs8060157 was 0.99 (95 %CI 0.73–1.34) and 1.00 (95 %CI 0.76–1.33) for rs10030044. In the placebo arm, the odds ratio was 1.10 (95 %CI 0.87–1.40) for rs8060157 and 1.01 (95 %CI 0.79–1.29) for rs10030044. There was no evidence to suggest that other SNPs in the surrounding regions of these SNPs might predict response to tamoxifen. Results from these two prevention trials do not support the earlier findings. rs8060157 in ZNF423 and rs10030044 near CTSO do not appear to predict response to tamoxifen.

Background Breast cancer familial risk clinics offer screening and preventive strategies. While BRCA1 / BRCA2 genetic testing provides important risk information for some women, panels of more common breast cancer risk genetic variants may have relevance to greater numbers of women with familial risk. Methods Three polygenic risk scores (PRS) based on 18 SNPs were investigated in a case–control study of women attending a familial risk clinic. PRS were derived from published general European population allele ORs and frequencies (18-SNPs (SNP18)). In women with BRCA1 / BRCA2 mutations, 3 SNPs/13 SNPs, respectively, generated the PRS estimates. In total, 364 incident breast cancer cases (112 with BRCA1/2 mutations) were matched with 1605 controls (691 BRCA1/2 ) by age last mammogram and BRCA1/2 genetic test result. 87 women with cancer before attendance were also considered. Logistic regression was used to measure PRS performance through ORs per IQR and calibration of the observed to expected (O/E) logarithm relative risk when unadjusted and adjusted for phenotypic risk factors assessed by the Tyrer-Cuzick (TC) model. Results SNP18 was predictive for non-carriers of BRCA1/2 mutations (IQR OR 1.55, 95% CI 1.29 to 1.87, O/E 96%). Findings were unaffected by adjustment from TC (IQR OR 1.56, 95% CI 1.29 to 1.89) or when prior cancers were included (IQR OR 1.55, 95% CI 1.30 to 1.87). There was some evidence to support polygenic scores with weights for individuals with BRCA1/2 mutations ( BRCA1 IQR OR 1.44, 95% CI 1.17 to 1.76; BRCA2 IQ OR 1.44, 95% CI 0.90 to 2.31). Conclusions PRS may be used to refine risk assessment for women at increased familial risk who test negative/have low likelihood of BRCA 1 /2 mutations. They may alter the recommended prevention strategy for many women attending family history clinics.

The sensitivity of testing BRCA1 and BRCA2 remains unresolved as the frequency of deep intronic splicing variants has not been defined in high-risk familial breast/ovarian cancer families. This variant category is reported at significant frequency in other tumour predisposition genes, including NF1 and MSH2. We carried out comprehensive whole gene RNA analysis on 45 high-risk breast/ovary and male breast cancer families with no identified pathogenic variant on exonic sequencing and copy number analysis of BRCA1/2. In addition, we undertook variant screening of a 10-gene high/moderate risk breast/ovarian cancer panel by next-generation sequencing. DNA testing identified the causative variant in 50/56 (89%) breast/ovarian/male breast cancer families with Manchester scores of ≥50 with two variants being confirmed to affect splicing on RNA analysis. RNA sequencing of BRCA1/BRCA2 on 45 individuals from high-risk families identified no deep intronic variants and did not suggest loss of RNA expression as a cause of lost sensitivity. Panel testing in 42 samples identified a known RAD51D variant, a high-risk ATM variant in another breast ovary family and a truncating CHEK2 mutation. Current exonic sequencing and copy number analysis variant detection methods of BRCA1/2 have high sensitivity in high-risk breast/ovarian cancer families. Sequence analysis of RNA does not identify any variants undetected by current analysis of BRCA1/2. However, RNA analysis clarified the pathogenicity of variants of unknown significance detected by current methods. The low diagnostic uplift achieved through sequence analysis of the other known breast/ovarian cancer susceptibility genes indicates that further high-risk genes remain to be identified.

Previous studies have suggested an association between a variant in the promoter region of the FSHR gene and diminished response to controlled ovarian hyperstimulation (COH) in women undergoing assisted reproduction. FSHR -29G>A was genotyped in 559 women undergoing their first cycle of COH for IVF/intracytoplasmic sperm injection (ICSI) using TaqMan allelic discrimination assay. Correlation and regression analysis was performed to assess the relationship between FSHR promoter genotypes and markers of ovarian reserve and measures of response to COH, including the number of oocytes retrieved, gonadotrophin dose used and the live-birth rate. There were no statistically significant differences between the genotype frequencies and the markers of ovarian reserve or the early measures of response to COH. However, the live-birth rate was higher for women carrying the variant A allele (odds ratio [OR] 1.37; 95% confidence interval [CI] 1.02–1.84 per allele). This relationship did not reach statistical significance after adjustment for the number of embryos transferred (OR 1.33; 95% CI 0.98–1.83 per allele). Results from this study do not provide evidence that the FSHR -29G>A variant can be used in the individualization of the treatment protocol for women undergoing IVF/ICSI.

Gorlin syndrome is an autosomal dominant disorder, characterized by multiple early-onset basal cell carcinomas (BCCs) and jaw keratocysts. Through association studies in cohorts of sporadic BCC, nine genetic variants have previously been identified to increase the risk of BCC. The nine SNPs were genotyped by Taqman allelic discrimination in 125 individuals with Gorlin syndrome. Kaplan-Meier survival curves and Cox proportional-Hazard regression analysis were applied to determine the association between genotypes and age of first BCC in individuals with Gorlin syndrome. The p.(Arg151Cys) variant in MC1R (rs1805007) was associated with an earlier median age of onset of BCC of 27 years (95% CI: 20-34) compared with 34 years (95% CI: 30-40) for wild-type individuals (hazard ratio (HR)=1.64, 95% CI: 1.04-2.58, P=0.034). The risk allele of the variant at the chromosome 5p15 locus encompassing TERT-CLPTM1L (rs401681) was also associated with an earlier median onset of BCC, 31 years (95% CI: 28-37) compared with 41 years (95% CI: 32-48, HR=1.44, 95% CI: 1.08-1.93, P=0.014). In individuals with a risk allele at either rs1805007 or rs401681 the median time to BCC was 31 years of age (95% CI: 28-34) compared with 44 years of age (95% CI: 38-53) in wild-type individuals (HR=2.48, 95% CI: 1.47-4.17, P=0.0002). Our findings may have implications for future personalized risk estimates and BCC screening strategies in individuals with Gorlin syndrome.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder where definite diagnosis can only be made postmortem, and for which the most promising peripheral markers of disease state and severity have been found in the cerebrospinal fluid. However, recent results suggest that differences in the levels of certain plasma proteins do exist between AD patients and non-demented controls (NDC). Herein, we undertook an untargeted discovery study using isobaric mass tagging to compare the plasma protein levels between slow cognitive declining AD patients, rapid cognitive declining AD patients (RCD) and NDC subjects. Subsequent relative quantification and statistical analysis identified a list of candidate proteins able to distinguish RCD from NDC groups based on multivariate analysis. Selected proteins were then validated by western blot analysis in an independent sample set of 60 AD and 35 NDC subjects. In this cohort, AD patients displayed significantly lower plasma gelsolin levels compared to NDC subjects. Additionally, gelsolin levels correlated with disease progression rate estimated by Mini-Mental Status Examination decline per year. In order to further investigate gelsolin expression, three different brain regions from an additional cohort of 23 subjects and their respective plasma samples were analysed. No significant change in brain gelsolin levels could be established between AD and control subjects. Interestingly, this study reveals yet another condition where plasma gelsolin levels are decreased and our findings, together with the reported interaction of gelsolin and amyloid-beta, makes plasma gelsolin an attractive candidate for further studies targeted at better understanding disease progression in AD.

Importance Single-nucleotide polymorphisms (SNPs) have demonstrated an association with breast cancer susceptibility, but there is limited evidence on how to incorporate them into current breast cancer risk prediction models. Objective To determine whether a panel of 18 SNPs (SNP18) may be used to predict breast cancer in combination with classic risk factors and mammographic density. Design, Setting, and Participants This cohort study enrolled a subcohort of 9363 women, aged 46 to 73 years, without a previous breast cancer diagnosis from the larger prospective cohort of the PROCAS study (Predicting Risk of Cancer at Screening) specifically to evaluate breast cancer risk-assessment methods. Enrollment took place from October 2009 through June 2015 from multiple population-based screening centers in Greater Manchester, England. Follow-up continued through January 5, 2017. Exposures Genotyping of 18 SNPs, visual-assessment percentage mammographic density, and classic risk assessed by the Tyrer-Cuzick risk model from a self-completed questionnaire at cohort entry. Main Outcomes and Measures The predictive ability of SNP18 for breast cancer diagnosis (invasive and ductal carcinoma in situ) was assessed using logistic regression odds ratios per interquartile range of the predicted risk. Results A total of 9363 women were enrolled in this study (mean [range] age, 59 [46-73] years). Of these, 466 were found to have breast cancer (271 prevalent; 195 incident). SNP18 was similarly predictive when unadjusted or adjusted for mammographic density and classic factors (odds ratios per interquartile range, respectively, 1.56; 95% CI, 1.38-1.77 and 1.53; 95% CI, 1.35-1.74), with observed risks being very close to expected (adjusted observed-to-expected odds ratio, 0.98; 95% CI, 0.69-1.28). A combined risk assessment indicated 18% of the subcohort to be at 5% or greater 10-year risk, compared with 30% of all cancers, 35% of interval-detected cancers, and 42% of stage 2+ cancers. In contrast, 33% of the subcohort were at less than 2% risk but accounted for only 18%, 17%, and 15% of the total, interval, and stage 2+ breast cancers, respectively. Conclusions and Relevance SNP18 added substantial information to risk assessment based on the Tyrer-Cuzick model and mammographic density. A combined risk is likely to aid risk-stratified screening and prevention strategies.

The human apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 3F (APOBEC3F [A3F]) and A3G proteins are effective inhibitors of infection by various retroelements and share ∼50% amino acid sequence identity. We therefore undertook comparative analyses of the protein and RNA compositions of A3F- and A3G-associated ribonucleoprotein complexes (RNPs). Like A3G, A3F is found associated with a complex array of cytoplasmic RNPs and can accumulate in RNA-rich cytoplasmic microdomains known as mRNA processing bodies or stress granules. While A3F RNPs display greater resistance to disruption by RNase digestion, the major protein difference is the absence of the Ro60 and La autoantigens. Consistent with this, A3F RNPs also lack a number of small polymerase III RNAs, including the RoRNP-associated Y RNAs, as well as 7SL RNA. Alu RNA is, however, present in A3F and A3G RNPs, and both proteins suppress Alu element retrotransposition. Thus, we define a number of subtle differences between the RNPs associated with A3F and A3G and speculate that these contribute to functional differences that have been described for these proteins.

Defective axonal transport has been proposed as an underlying mechanism that may give rise to neurodegeneration. We investigated the effect of phosphorylation on the axonal transport of tau, a neuronal protein that stabilizes microtubules and is hyperphosphorylated and mislocalized in Alzheimer's disease. We report here that specific inhibition of glycogen synthase kinase-3 (GSK-3) reduces tau phosphorylation and significantly decreases the overall rate of axonal transport of tau in rat cortical neurons. Tau mutants, with serine/threonine targets of GSK-3 mutated to glutamate to mimic a permanent state of phosphorylation, were transported at a significantly increased rate compared to wild-type tau. Conversely, tau mutants, in which alanine replaced serine/threonine to mimic permanent dephosphorylation, were transported at a decreased rate compared to wild-type tau. We also found that tau interacts with the light chain of kinesin-1 and that this is dependent on the phosphorylation state of tau. Tau phosphorylation by GSK-3 increased binding, and dephosphorylated tau exhibited a reduced association with kinesin-1. We conclude that GSK-3 phosphorylation of tau modulates its axonal transport by regulating binding to kinesin-1. Hyperphosphorylated tau in Alzheimer's disease appearing first in distal portions of axons may result from aberrant axonal transport of phosphorylated tau reported here.

Tau in Alzheimer disease brain is highly phosphorylated and aggregated into paired helical filaments comprising characteristic neurofibrillary tangles. Here we have analyzed insoluble Tau (PHF-tau) extracted from Alzheimer brain by mass spectrometry and identified 11 novel phosphorylation sites, 10 of which were assigned unambiguously to specific amino acid residues. This brings the number of directly identified sites in PHF-tau to 39, with an additional six sites indicated by reactivity with phosphospecific antibodies to Tau. We also identified five new phosphorylation sites in soluble Tau from control adult human brain, bringing the total number of reported sites to nine. To assess which kinases might be responsible for Tau phosphorylation, we used mass spectrometry to determine which sites were phosphorylated in vitro by several kinases. Casein kinase 1delta and glycogen synthase kinase-3beta were each found to phosphorylate numerous sites, and each kinase phosphorylated at least 15 sites that are also phosphorylated in PHF-tau from Alzheimer brain. A combination of casein kinase 1delta and glycogen synthase kinase-3beta activities could account for over three-quarters of the serine/threonine phosphorylation sites identified in PHF-tau, indicating that casein kinase 1delta may have a role, together with glycogen synthase kinase-3beta, in the pathogenesis of Alzheimer disease.

STAT (signal transducer and activator of transcription) proteins are critical regulators of cytokine-induced cell proliferation, differentiation and survival. STAT functional activity can be variably regulated by post-translational modifications, including phosphorylation, acetylation, methylation and sumoylation. Additionally, limited proteolytic digestion of full-length STAT proteins (STATalpha) generates C-terminally truncated forms (STATgamma) in different cell lineages, which have significantly reduced transcriptional activity due to the lack of the transactivation domain. Previously, it has been shown that STAT5gamma, generated by an unidentified nuclear serine protease, plays an important role in myeloid cell differentiation and is aberrantly expressed in acute myeloid leukaemia. To better understand this regulatory mechanism for STAT5 function, we have purified the STAT5 protease from the immature myeloid cell line 32D and identified it by MS analysis as the granule-derived serine protease, CatG (cathepsin G). We show that purified CatG can specifically cleave full-length STAT5 to generate STAT5gamma, and this activity can be inhibited by AEBSF [4-(2-aminoethyl)benzenesulfonyl fluoride] in an in vitro protease assay. Importantly, preparation of nuclear and cytoplasmic extracts from immature myeloid cell lines, 32D and FDC-P1, in the presence of a specific inhibitor for CatG results in the identification of STAT5alpha only. These studies indicate that nuclear STAT5gamma does not naturally exist in immature myeloid cells and is artificially generated from STAT5alpha during the preparation of extracts due to the abundance of CatG in these cells. Therefore in contrast with earlier studies, our data suggest that STAT5alpha, rather than STAT5gamma is the active form in immature myeloid cells.

Members of the APOBEC (apolipoproteinBmRNA-editing enzymecatalytic polypeptide 1-like) family of cytidine deaminases inhibit host cell genome invasion by exogenous retroviruses and endogenous retrotransposons. Because these enzymes can edit DNA or RNA and potentially mutate cellular targets, their activities are presumably regulated; for instance, APOBEC3G (A3G) recruitment into high-molecular-weight ribonucleoprotein (RNP) complexes has been shown to suppress its enzymatic activity. We used tandem affinity purification together with mass spectrometry (MS) to identify protein components within A3G-containing RNPs. We report that numerous cellular RNA-binding proteins with diverse roles in RNA function, metabolism, and fate determination are present in A3G RNPs but that most interactions with A3G are mediated via binding to shared RNAs. Confocal microscopy demonstrated that substantial quantities of A3G localize to cytoplasmic microdomains that are known as P bodies and stress granules (SGs) and are established sites of RNA storage and metabolism. Indeed, subjecting cells to stress induces the rapid redistribution of A3G and a number of P-body proteins to SGs. Among these proteins are Argonaute 1 (Ago1) and Argonaute 2 (Ago2), factors that are important for RNA silencing and whose interactions with A3G are resistant to RNase treatment. Together, these findings reveal that A3G associates with RNPs that are found throughout the cytosol as well as in discrete microdomains. We also speculate that the interplay between A3G, RNA-silencing pathways, and cellular sites of RNA metabolism may contribute to A3G's role as an inhibitor of retroelement mobility and as a possible regulator of cellular RNA function.

PUBLISHED, Rac and its downstream effectors p21-activated kinase (PAK) family kinases regulate actin dynamics within growth cones to control neurite outgrowth during development. The activity of Rac is stimulated by guanine nucleotide exchange factors (GEFs) that promote GDP release and GTP binding. ALS2/Alsin is a recently described GEF that contains a central domain that is predicted to regulate the activities of Rac and/or Rho and Cdc42 activities. Mutations in ALS2 cause some recessive familial forms of amyotrophic lateral sclerosis (ALS) but the function of ALS2 is poorly understood. Here we demonstrate that ALS2 is present within growth cones of neurons, in which it co-localizes with Rac. Furthermore, ALS2 stimulates Rac but not Rho or Cdc42 activities, and this induces a corresponding increase in PAK1 activity. Finally, we demonstrate that ALS2 promotes neurite outgrowth. Defects in these functions may therefore contribute to motor neuron demise in ALS., This work was supported by grants from the Medical Research Council and Wellcome Trust (to C. C. J. M.). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked ?advertisement? in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

Systemic sclerosis (SSc) is characterized by progressive microvascular damage, immune system activation, and widespread fibrosis. The gene Three prime Repair EXonuclease 1 (TREX1) encodes a DNA 3ʹ ...

Biotin-cysteine was used to study protein S-thiolation in isolated rat kidneys subjected to ischemia and reperfusion. After 40 min of ischemia, total protein S-thiolation increased significantly (P0.05), by 311%, and remained significantly elevated (P0.05), 221% above control, after 5 min of postischemic reperfusion. Treatment of protein samples with 2-mercaptoethanol abolished the S-thiolation signals detected, consistent with the dependence of the signal on the presence of a disulfide bond. With the use of gel filtration chromatography followed by affinity purification with streptavidin-agarose, S-thiolated proteins were purified from CHAPS-soluble kidney homogenate. The proteins were then separated by SDS-PAGE and stained with Coomassie blue. With a combination of matrix-assisted laser desorption ionization time of flight mass spectrometry and LC/MS/MS analysis of protein bands digested with trypsin, a number of S-thiolation substrates were identified. These included the LDL receptor-related protein 2, ATP synthase alpha chain, heat shock protein 90 beta, hydroxyacid oxidase 3, serum albumin precursor, triose phosphate isomerase, and lamin. These represent proteins that may be functionally regulated by S-thiolation and thus could undergo a change in activity or function after renal ischemia and reperfusion.

The objective of this study was to assess the role of the variant p.Asn680Ser in the FSH receptor gene (FSHR) in determining oocyte maturity. It also assessed the relationship between this FSHR variant with metaphase-II oocyte output rate (MOR) and the fertilization rate. This was a prospective observational study based at a tertiary referral centre for reproductive medicine. Women (n=212) undergoing their first cycle of ovarian stimulation for IVF with intracytoplasmic sperm injection (ICSI) were included in the study. Baseline pelvic ultrasound and blood tests were taken on day 2 or 3 of the cycle for assessment of baseline hormones and for DNA extraction. Genotypes for FSHR p.Asn680Ser was determined using TaqMan allelic discrimination assay. The outcome measures were the total dose of exogenous gonadotrophins used, antral follicle count (AFC), number of mature (metaphase-II) oocytes retrieved, MOR and fertilization rate. No statistically significant differences were found between the number of mature oocytes retrieved, MOR or fertilization rates among the patients with different p.Asn680Ser FSHR genotypes. No significant difference was noted in the clinical pregnancy rates per transfer. There is no evidence that the p.Asn680Ser FSHR genotype predicts oocyte maturity.

Background Tau protein is the principal component of the neurofibrillary tangles found in Alzheimer's disease, where it is hyperphosphorylated on serine and threonine residues, and recently phosphotyrosine has been demonstrated. The Src-family kinase Fyn has been linked circumstantially to the pathology of Alzheimer's disease, and shown to phosphorylate Tyr18. Recently another Src-family kinase, Lck, has been identified as a genetic risk factor for this disease. Results In this study we show that Lck is a tau kinase. In vitro, comparison of Lck and Fyn showed that while both kinases phosphorylated Tyr18 preferentially, Lck phosphorylated other tyrosines somewhat better than Fyn. In co-transfected COS-7 cells, mutating any one of the five tyrosines in tau to phenylalanine reduced the apparent level of tau tyrosine phosphorylation to 25-40% of that given by wild-type tau. Consistent with this, tau mutants with only one remaining tyrosine gave poor phosphorylation; however, Tyr18 was phosphorylated better than the others. Conclusions Fyn and Lck have subtle differences in their properties as tau kinases, and the phosphorylation of tau is one mechanism by which the genetic risk associated with Lck might be expressed pathogenically.

Tandem Mass Tags (TMT) are suited to both global and targeted quantitation approaches of proteins and peptides. Different versions of these tags allow for the generation of both isobaric and isotopic sets of reagents sharing the same common structure. This feature allows for a straightforward transfer of data obtained during discovery studies into targeted investigations. In prior discovery studies, an isobaric set of these reagents was used to identify Neisseria meningitidis proteins expressed under iron-limitation. Here, we apply isotopic versions of those reagents in combination with single reaction monitoring to verify selected candidates found to be differentially regulated in these discovery studies, representing both well-known and novel iron-regulated proteins, such as the MtrCDE drug efflux pump. In this targeted approach (TMT-SRM), the selectivity of SRM is maintained while allowing the incorporation of an internal reference standard into the experiment. By monitoring 184 transitions, TMT-SRM resulted in the quantitation of 33 peptides representing 12 proteins. The acquired data corroborated the results obtained during the discovery phase. Furthermore, these data obtained by MS-based quantitation of peptides were independently confirmed by western blotting results, an orthogonal approach based on quantitation at the protein level.

Background Metacarpal 4-5 fusion (MF4) is a rare congenital hand malformation characterised primarily by ulnar deviation of the fifth finger, clinodactyly, shortening of the fifth metacarpal and reduced mobility of the fifth finger. A small number of familial cases have been described in the literature, consistent with X-linked recessive inheritance. In May 2013 causative mutations in the FGF16 gene were identified in two unrelated patients with MF4.[1] This prompted the sequencing of FGF16 in half-brothers with MF4, with a view to identifying a possibly causative mutation.

Alzheimer's disease is a common and devastating disease for which there is no readily available biomarker to aid diagnosis or to monitor disease progression. Biomarkers have been sought in CSF but no previous study has used two-dimensional gel electrophoresis coupled with mass spectrometry to seek biomarkers in peripheral tissue. We performed a case-control study of plasma using this proteomics approach to identify proteins that differ in the disease state relative to aged controls. For discovery-phase proteomics analysis, 50 people with Alzheimer's dementia were recruited through secondary services and 50 normal elderly controls through primary care. For validation purposes a total of 511 subjects with Alzheimer's disease and other neurodegenerative diseases and normal elderly controls were examined. Image analysis of the protein distribution of the gels alone identifies disease cases with 56% sensitivity and 80% specificity. Mass spectrometric analysis of the changes observed in two-dimensional electrophoresis identified a number of proteins previously implicated in the disease pathology, including complement factor H (CFH) precursor and alpha-2-macroglobulin (alpha-2M). Using semi-quantitative immunoblotting, the elevation of CFH and alpha-2M was shown to be specific for Alzheimer's disease and to correlate with disease severity although alternative assays would be necessary to improve sensitivity and specificity. These findings suggest that blood may be a rich source for biomarkers of Alzheimer's disease and that CFH, together with other proteins such as alpha-2M may be a specific markers of this illness.