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Notwithstanding several research efforts in the past years, robust and replicable molecular signatures for autism spectrum disorders from peripheral blood remain elusive. The available literature on blood transcriptome in ASD suggests that through accurate experimental design it is possible to extract important information on the disease pathophysiology at the peripheral level. Here we exploit the availability of a resource for molecular biomarkers in ASD, the Italian Autism Network (ITAN) collection, for the investigation of transcriptomic signatures in ASD based on a discordant sibling pair design. Whole blood samples from 75 discordant sibling pairs selected from the ITAN network where submitted to RNASeq analysis and data analyzed by complementary approaches. Overall, differences in gene expression between affected and unaffected siblings were small. In order to assess the contribution of differences in the relative proportion of blood cells between discordant siblings, we have applied two different cell deconvolution algorithms, showing that the observed molecular signatures mainly reflect changes in peripheral blood immune cell composition, in particular NK cells. The results obtained by the cell deconvolution approach are supported by the analysis performed by WGCNA. Our report describes the largest differential gene expression profiling in peripheral blood of ASD subjects and controls conducted by RNASeq. The observed signatures are consistent with the hypothesis of immune alterations in autism and an increased risk of developing autism in subjects exposed to prenatal infections or stress. Our study also points to a potential role of NMUR1, HMGB3, and PTPRN2 in ASD.

METHODS: The Italian Public Health Institute (Istituto Superiore di Sanità) sent six validated DNA samples to participating laboratories: technical and clinical information was provided for each sample. Laboratories were required to analyse all six samples. For each sample the laboratories had to provide the results (including raw data) and a report of molecular analysis within 2 months using current methods and nomenclature. Raw data and reports were evaluated by a Steering Committee and their comments were sent to each laboratory. RESULTS: Genotyping results indicated a general good level of quality for all laboratories, i.e., approximately 1% of alleles were incorrectly assigned each year due to analytical (45%) and misinterpretation (45%) errors. During the first 2 years, more than 70% of laboratories did not test for some regional Italian mutations. Commercial kits for reverse dot-blot and oligonucleotide ligation assay PCR were used to detect mutations by 52.8% and 29.5%, respectively, of the participating laboratories. Reporting of results was still inadequate; in 2004 a model for the written report was introduced, but not all laboratories used it. CONCLUSIONS: Our data show that few genotyping errors were made by laboratories and were principally due to misinterpretation and analytical reasons. However, reports are still inadequate and it will be interesting to evaluate the introduction of the reporting model in future years.

We performed a genome-wide association study on 1,292 individuals with abdominal aortic aneurysms (AAAs) and 30,503 controls from Iceland and The Netherlands, with a follow-up of top markers in up to 3,267 individuals with AAAs and 7,451 controls. The A allele of rs7025486 on 9q33 was found to associate with AAA, with an odds ratio (OR) of 1.21 and P = 4.6 x 10(-10). In tests for association with other vascular diseases, we found that rs7025486[A] is associated with early onset myocardial infarction (OR = 1.18, P = 3.1 x 10(-5)), peripheral arterial disease (OR = 1.14, P = 3.9 x 10(-5)) and pulmonary embolism (OR = 1.20, P = 0.00030), but not with intracranial aneurysm or ischemic stroke. No association was observed between rs7025486[A] and common risk factors for arterial and venous diseases-that is, smoking, lipid levels, obesity, type 2 diabetes and hypertension. Rs7025486 is located within DAB2IP, which encodes an inhibitor of cell growth and survival.

Background The platelet P2Y12 receptor plays a key role in platelet activation. The H2 haplotype of the P2Y12 receptor gene (P2RY12) has been found to be associated with maximal aggregation response to adenosine diphosphate (ADP) and with increased risk for peripheral arterial disease. No data are available on its association with coronary artery disease (CAD). Methods The H2 haplotype of the P2RY12 was determined in 1378 unrelated patients of both sexes selected according to the presence of significant coronary artery disease (CAD group) or having normal coronary angiogram at cardiac catheterization (CAD-free group). Significant coronary artery disease was angiographically determined, and was defined as a greater than 50% visually estimated luminal diameter stenosis in at least one major epicardial coronary artery. Results In the studied population 71.9% had CAD (n = 991) and 28.1% had normal coronary angiogram (n = 387). H2 haplotype carriers were more frequent in the CAD group (p = 0.03, OR = 1.36, 95%CI = 1.02–1.82). The H2 haplotype was significantly associated with CAD in non-smokers (p = 0.007, OR = 1.83 95%CI = 1.17–2.87), but not in smokers. The association remained significant after adjustment for other covariates (age, triglycerides, HDL, hypertension, diabetes) by multivariate logistic regression (p = 0.004, OR = 2.32 95%CI = 1.30–4.15). Conclusion Gene sequence variations of the P2Y12 receptor gene are associated with the presence of significant CAD, particularly in non-smoking individuals.

An abbreviated tract of five thymidines (5T) in intron 8 of the cystic fibrosis transmembrane conductance regulator ( CFTR) gene is found in similar to 10% of individuals in the general population. When found in trans with a severe CFTR mutation, 5T can result in male infertility, nonclassic cystic fibrosis, or a normal phenotype. To test whether the number of TG repeats adjacent to 5T influences disease penetrance, we determined TG repeat number in 98 patients with male infertility due to congenital absence of the vas deferens, 9 patients with nonclassic CF, and 27 unaffected individuals ( fertile men). Each of the individuals in this study had a severe CFTR mutation on one CFTR gene and 5T on the other. Of the unaffected individuals, 78% ( 21 of 27) had 5T adjacent to 11 TG repeats, compared with 9% ( 10 of 107) of affected individuals. Conversely, 91% ( 97 of 107) of affected individuals had 12 or 13 TG repeats, versus only 22% ( 6 of 27) of unaffected individuals (P < .00001). Those individuals with 5T adjacent to either 12 or 13 TG repeats were substantially more likely to exhibit an abnormal phenotype than those with 5T adjacent to 11 TG repeats ( odds ratio 34.0, 95% CI 11.1 - 103.7, P < .00001). Thus, determination of TG repeat number will allow for more accurate prediction of benign versus pathogenic 5T alleles.

We report a large genomic deletion of the cystic fibrosis transmembrane conductance regulator (CFTR) gene, viz.. a deletion that is frequently observed in Central and Eastern Europe. The mutation, termed CFTRdele2.3(21 kb), deletes 21,080 bp spanning introns 1-3 of the CFTR gene. Transcript analyses have revealed that this deletion results in the loss of exons 2 and 3 in epithelial CFTR mRNA, thereby producing a premature termination signal within exon 4. In order to develop a simple polymerase chain reaction assay for this allele, we defined the end-points of the deletion at the DNA sequence level. We next screened for this mutation in a representative set of European and European-derived populations. Some 197 CF patients, including seven homozygotes, bearing this mutation have been identified during the course of our study. Clinical evaluation of CFTRdele2.3(21 kb) homozygotes and a comparison of compound heterozygotes for Delta F508/CFTRdele2,3(21 kb) with pairwise-matched Delta F508 homozygotes indicate that this deletion represents a severe mutation associated with pancreatic insufficiency and early age at diagnosis. Current data show that the mutation is particularly common in Czech (6.4% of all CF chromosomes), Russian (5.2%), Belorussian (3.3%). Austrian (2.6%), German (1.5%), Polish (1.5%), Slovenian (1.5%), Ukrainian (1.2%), and Slovak patients (1.1%). It has also been found in Lithuania, Latvia, Macedonia and Greece and has sporadically been observed in Canada, USA, France, Spain, Turkey, and UK, but not in CF patients from Bulgaria, Croatia, Romania or Serbia. Haplotype analysis has identified the same extragenic CF-haplotype: XV-2c/KM. 19 “A” and the same infrequent intragenic microsatellite haplotype 16-33-13 (IVS8CA-IVS17bTA-IVSI7bCA) in all examined CFTRdele2,3(21 kb) chromosomes, suggesting a common origin for this deletion. We conclude that the 21-kb deletion is a frequent and severe CF mutation in populations of Eastern- and Western-Slavic descent.

The N1303K mutation was identified in the second nucleotide binding fold of the cystic fibrosis (CF) gene last year. We have gathered data from laboratories throughout Europe and the United States of America in order to estimate its frequency and to attempt to characterise the clinical manifestations of this mutation. N1303K, identified on 216 of nearly 15000 CF chromosomes tested, accounts for 1.5% of all CF chromosomes. The frequency of the N1303K allele varies significantly between countries and ethnic groups, being more common in Southern than in Northern Europe. This variation is independent of the DELTA-F508 allele. It was not found on UK Asian, American Black or Australian chromosomes. N1303K is associated with four different linked marker haplotypes for the polymorphic markers XV-2c, KM.19 and pMP6d-9. Ten patients are homozygous for this mutation, whereas 106 of the remainder carry one of 12 known CF mutations in the other CF allele. We classify N1303K as a “severe” mutation with respect to the pancreas, but can find no correlation between this mutation, in either the homozygous or heterozygous state, and the severity of lung disease.

The suppression of Ph1-positive hemopoiesis is a major goal in the treatment of CML; in this context the CML patients in blast crisis obtaining a complete clinical remission represent a useful model to investigate the behavior of the Ph1-positive and negative clones during bone marrow repopulation after ablative therapy.Seven CML patients in blast crisis (four lymphoid and three myeloid) who obtained a complete clinical remission after an intensive polychemotherapy treatment were evaluated by cytogenetic and molecular analysis both in blast and remission phases. Standard cytogenetic and Southern techniques were employed; in addition, minimal residual disease status (MRD) was ascertained by amplification (PCR) of the specific bcr-abl chimeric transcripts.After a single cycle of induction, all lymphoid cases displayed a complete restoration of Ph1-negative hemopoiesis; by contrast, one myeloid blast crisis showed a partial suppression of Ph1-positive hemopoiesis only after two cycles of chemotherapy, and in the remaining two cases the hematological remission was indeed a reversion to the chronic phase.Ph1-positive chronic clones present in lymphoid blast crisis showed a higher degree of sensitivity to intensive chemotherapy than those present in the myeloid cases. This observation further suggests that the growth properties of the Ph1-positive clones are highly variable from case to case and probably tend to progress during the time-course of the disease.

Positional cloning involves first finding linkage between an inherited phenotype (such as a disease) and a DNA marker, followed by the use of a variety of physical and genetic mapping techniques to move from linkage to mutation. If there is a founder effect within a population, crossovers are often rare between the mutation causing the phenotype and closely situated markers and increasing disequilibrium may be observed as the site of the mutation is approached. Standard coefficients of disequilibrium may, however, be insensitive to the relative position of close markers and the mutation, because they depend upon allele frequencies in the normal population compared to those of the founder chromosome. Using cystic fibrosis in European populations as a model system, alternative methods for determining the position of a mutation are discussed. These include haplotype parsimony and three-way interval likelihood analysis. Both methods predict the location of the major CF mutation accurately from a real set of more than 600 European CF chromosomes.

Chronic pancreatitis is a common inflammatory disease of the pancreas. Mutations in the genes encoding cationic trypsinogen (PRSS1) and the pancreatic secretory trypsin inhibitor (SPINK1) are associated with chronic pancreatitis. Because increased proteolytic activity owing to mutated PRSS1 enhances the risk for chronic pancreatitis, mutations in the gene encoding anionic trypsinogen (PRSS2) may also predispose to disease. Here we analyzed PRSS2 in individuals with chronic pancreatitis and controls and found, to our surprise, that a variant of codon 191 (G191R) is overrepresented in control subjects: G191R was present in 220/6,459 (3.4%) controls but in only 32/2,466 (1.3%) affected individuals (odds ratio 0.37; P = 1.1 x 10(-8)). Upon activation by enterokinase or trypsin, purified recombinant G191R protein showed a complete loss of trypsin activity owing to the introduction of a new tryptic cleavage site that renders the enzyme hypersensitive to autocatalytic proteolysis. In conclusion, the G191R variant of PRSS2 mitigates intrapancreatic trypsin activity and thereby protects against chronic pancreatitis. The initial experiments were supported by the DFG (Wi 2036/1-1). This work was supported by the Sonnenfeld-Stiftung, Berlin, Germany (to H.W.), the US National Institutes of Health (NIH) (grant DK058088 to M.S.-T.), INSERM (Institut National de la Santé et de la Recherche Médicale) and the Programme Hospitalier de Recherche Clinique (grant PHRC R 08-04 to C.F.)

OBJECTIVE: The objective of this study was to replicate an association study on a newly collected Italian autism spectrum disorder (ASD) cohort by studying the genetic markers associated with ASDs from recent genome-wide and candidate gene association studies. METHODS: We have genotyped 746 individuals from 227 families of the Italian Autism Network using allelic discrimination TaqMan assays for seven common single-nucleotide polymorphisms: rs2292813 (SLC25A12 gene), rs35678 (ATP2B2 gene), rs4307059 (between CDH9 and CDH10 genes), rs10513025 (between SEMA5A and TAS2R1 genes), rs6872664 (PITX1 gene), rs1861972 (EN2 gene), and rs4141463 (MACROD2 gene). A family-based association study was conducted. RESULTS: A significant association was found for two of seven markers: rs4307059 T allele (odds ratio: 1.758, SE=0.236; P-value=0.017) and rs35678 TC genotype (odds ratio: 0.528, SE=0.199; P-value=0.0013). CONCLUSION: A preferential allele transmission of two markers located at loci previously associated with social and verbal communication skill has been confirmed in patients of a new ASD family sample.

Background Mutation epidemiology in each ethnic group is a crucial step of strategies for cystic fibrosis (CF) diagnosis and counselling. To date, the scanning of the whole coding region of the cystic fibrosis transmembrane conductance regulator (CFTR) gene permits to identify about 90% of alleles from patients bearing CF and a lower percentage in patients bearing atypical CF. CFTR rearrangements in heterozygosis elude current techniques for molecular analysis, and some of them have been reported with a frequency up to 6% in various ethnic groups. Methods Using quantitative PCR analysis of all coding regions, we assessed the occurrence of CFTR rearrangements in 130 alleles from classic CF patients and in 198 alleles from atypical CF patients (all unrelated and from Italian descent) bearing unidentified mutations after the scanning of CFTR. Results Seven rearrangements (i.e., dele1, dele2, dele2_3, dele 14b_17b, dele17a_18, dele22_23, and dele22_24) were identified in 34/131 (26.0%) CF alleles bearing undetected mutations (which means about 2.5% of all CF alleles) and in none of the 198 alleles from atypical CF. The CFTR haplotype and the sequence analysis of the breakpoints confirmed the common origin of all the rearrangements. Thus, we set up a novel duplex PCR assay for the large-scale analysis of the seven rearrangements. The procedure was rapid (all PCR amplifications were obtained under the same conditions), costless and repeatable. Conclusions It is useful to select the CFTR rearrangements more frequent in specific ethnic groups and to set up procedures for large-scale analysis. Their study can be performed in cases in which a high detection rate is required (i.e., partners of CF carriers/patients). On the contrary, the analysis of rearrangement is useless in atypical CF patients.

The etiology of chronic obstructive pulmonary disease (COPD) is still unknown, and both genetic and environmental factors may play a role. Some clinical aspects of COPD occur similarly in cystic fibrosis (CF), particularly in adult patients. A DNA polymorphic marker in strong linkage disequilibrium with the CF locus has been used to check the hypothesis that mutations of this locus might be involved in COPD. Its allele frequencies have been found to be in equilibrium in COPD patients as well as in appropriate control subjects. The determinants possibly involved in genetic predisposition to COPD therefore do not seem to comprise CF gene mutations.

Three polymorphic DNA marker loci (INT1L1, D7S23 and D7S399) map to a chromosomal region that is very close to the cystic fibrosis (CF) locus in terms of genetic distance. These marker loci have been used to analyse the linkage disequilibrium in 137 CF families from two South European countries (Italy and Spain). The markers can be analysed for differences in linkage disequilibrium more easily in these populations than in North Europeans, in whom the disequilibrium between the allelic systems defined by the probes and CF is much greater and on a "plateau" through the genetic region. The different levels of disequilibrium found in the studied populations suggest that D7S399 and D7S23 are both closer to CF than INT1L1, and provide additional information on the origins and homogeneity of the CF defect.