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To evaluate choroidal vascularity index (CVI), choroidal thickness, choroidal volume, and choroidal intensity in subjects with nonneovascular age-related macular degeneration (NNVAMD) with and without reticular pseudodrusen (RPD).We included 60 eyes of 35 subjects with NNVAMD (including 30 eyes of 18 subjects with RPD) and 30 eyes of 17 age-matched healthy individuals from the ongoing Amish Eye study. The choroid was segmented from dense volume spectral domain optical coherence tomography scans and choroidal thickness (microns), choroidal intensity (log units), and choroidal volume (mm) from the entire macula (6 × 6 mm) were computed. A central horizontal B-scan was binarized and the luminal and stromal portions of the choroid were segmented. Choroidal vascularity index (%) was calculated as the ratio of luminal area to total choroid area. Choroidal parameters were compared between the groups by pairwise comparisons using the Student's t-test.The CVI was significantly lower in healthy eyes compared to those with RPD (53.43 ± 8.51 vs. 54.76 ± 4.83, P0.001). The CVI was also significantly lower in NNVAMD eyes without RPD compared to those with RPD (50.09 ± 7.51 vs. 54.76 ± 4.83, P = 0.006). There was no difference in CVI between healthy eyes and NNVAMD eyes without RPD (P = 0.84). Choroidal thickness and choroidal volume were significantly higher in NNVAMD without RPD (P0.05); and significantly lower in NNVAMD with RPD (P0.05) when compared with normal eyes. Choroidal intensity was significantly higher in NNVAMD with RPD when compared with normal eyes (P = 0.02) and NNVAMD eyes without RPD (P = 0.001).Multiple choroidal parameters reflecting the status of the choroidal vasculature and stroma seem to be altered in eyes with RPD compared with both normal eyes and NNVAMD eyes without RPD. These findings may provide insights into the pathophysiology of RPD.

ObjectiveHere, we re-examineTOMM40-523′ as a race/ethnicity-specific risk modifier for late-onset Alzheimer disease (LOAD) with adjustment for local genomic ancestry (LGA) inApolipoprotein E(APOE) ε4 haplotypes.MethodsTheTOMM40-523′ size was determined by fragment analysis and whole genome sequencing in homozygousAPOE ε3 andAPOE ε4 haplotypes of African (AF) or European (EUR) ancestry. The risk for LOAD was assessed within groups by allele size.ResultsTheTOMM40-523′ length did not modify risk for LOAD inAPOE ε4haplotypes with EUR or AF LGA. Increasing length ofTOMM40-523′ was associated with a significantly reduced risk for LOAD in EURAPOEε3 haplotypes.ConclusionsAdjustment for LGA confirms thatTOMM40-523′ cannot explain the strong differential risk for LOAD betweenAPOEε4 with EUR and AF LGA. Our study does confirm previous reports that increasing allele length of theTOMM40-523′repeat is associated with decreased risk for LOAD in carriers of homozygousAPOEε3 alleles and demonstrates that this effect is occurring in those individuals with the EUR LGAAPOEε3 allele haplotype.

Background— ECG QRS duration, a measure of cardiac intraventricular conduction, varies ≈2-fold in individuals without cardiac disease. Slow conduction may promote re-entrant arrhythmias. Methods and Results— We performed a genome-wide association study to identify genomic markers of QRS duration in 5272 individuals without cardiac disease selected from electronic medical record algorithms at 5 sites in the Electronic Medical Records and Genomics (eMERGE) network. The most significant loci were evaluated within the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium QRS genome-wide association study meta-analysis. Twenty-three single-nucleotide polymorphisms in 5 loci, previously described by CHARGE, were replicated in the eMERGE samples; 18 single-nucleotide polymorphisms were in the chromosome 3 SCN5A and SCN10A loci, where the most significant single-nucleotide polymorphisms were rs1805126 in SCN5A with P =1.2×10 −8 (eMERGE) and P =2.5×10 −20 (CHARGE) and rs6795970 in SCN10A with P =6×10 −6 (eMERGE) and P =5×10 −27 (CHARGE). The other loci were in NFIA , near CDKN1A , and near C6orf204. We then performed phenome-wide association studies on variants in these 5 loci in 13859 European Americans to search for diagnoses associated with these markers. Phenome-wide association study identified atrial fibrillation and cardiac arrhythmias as the most common associated diagnoses with SCN10A and SCN5A variants. SCN10A variants were also associated with subsequent development of atrial fibrillation and arrhythmia in the original 5272 “heart-healthy” study population. Conclusions— We conclude that DNA biobanks coupled to electronic medical records not only provide a platform for genome-wide association study but also may allow broad interrogation of the longitudinal incidence of disease associated with genetic variants. The phenome-wide association study approach implicated sodium channel variants modulating QRS duration in subjects without cardiac disease as predictors of subsequent arrhythmias.

Objective: Peripheral neuropathy (PN) often complicates nucleoside reverse transcriptase inhibitor (NRTI) therapy of HIV infection and may involve mitochondrial dysfunction. Since iron deficiency is associated with some types of PN, and iron is essential for mitochondrial function, we tested the hypothesis that hemochromatosis (HFE) gene mutations influence susceptibility to NRTI-induced PN. Design: Case-control study involving multicenter, AIDS Clinical Trials Group (ACTG) protocol 384 and ACTG Human DNA Repository specimens. Methods: Study participants were randomized to receive three- or four-drug antiretroviral therapy with didanosine (ddl) plus stavudine (d4T) or zidovudine plus lamivudine, given with efavirenz, nelfinavir, or both, with up to three years of follow-up. PN was ascertained based on signs and symptoms. HFE C282Y and H63D genotypes were determined, and associations with PN were assessed using logistic regression. Results: Of 509 participants, 147 (29%) developed PN, 73% of whom had been randomized to receive ddl plus d4T. Among ddl/d4T-ever-treated individuals, HFE C282Y heterozygotes developed PN on ddl/d4T significantly less often than C282Y non-carriers, adjusting for age, CD4 lymphocyte count and viral load at baseline, and concomitant antiretroviral drugs [6% vs. 35%, respectively, in whites; adjusted odds ratio (OR), 0.17; 95% confidence interval (Cl) 0.03-0.83; P = 0.021]. Regardless of race/ethnicity, ddl/d4T-associated PN was uncommon in C282Y heterozygotes [race-adjusted OR, 0.30; 95% CI 0.09-0.96); P = 0.042]. Conclusions: Iron-loading HFE mutations such as C282Y are associated with a decreased risk of PN during antiretroviral therapy. This finding has potential implications for the prediction and prevention of NRTI-associated PN, particularly in populations at risk of iron deficiency.

Background: Previous linkage studies have shown that chromosome 12 harbors susceptibility genes for late-onset Alzheimer disease (LOAD). However, association studies of several candidate genes on this chromosome region have produced ambiguous results. A recent study reported the association between the glyceraldehyde-3-phosphate dehydrogenase ( GAPD ) gene on chromosome 12p and the risk of LOAD. Methods: The authors conducted family-based and case-control association studies in two independent LOAD data sets on 12 single-nucleotide polymorphisms (SNPs) in the GAPD gene and its paralogs. Results: No association was found of the GAPD gene with LOAD in the family-based data set, but marginal evidence of association was seen in the later-onset subgroup when age at onset was stratified. The SNP rs2029721 in one GAPD pseudogene was also found to be associated with risk for LOAD in the unrelated case-control data set ( p = 0.003). Conclusions: The GAPD gene and its pseudogene may play a role in the development of late-onset Alzheimer disease. However, the effect, if any, is likely to be limited.

Background: Paraoxonases (PONs) are involved in the detoxification of organophosphate pesticides and chemical nerve agents. Due to a reported possible twofold increased risk of ALS in Gulf War veterans and the associations of PON1 polymorphisms with the neurologic symptom complex of the Gulf War syndrome, the authors investigated the association between sporadic ALS (SALS) and PON gene cluster variants in a large North American Caucasian family–based and case-control cohort (N = 1,891). Methods: Clinically definite and probable ALS was diagnosed according to the revised El Escorial criteria, exclusion of family history of ALS, and SOD1 mutation analysis. Single nucleotide polymorphism (SNP) genotyping was done using Taq Man assays on ABI7900HT. Data were analyzed using SPSS, Haploview, FBAT, and THESIAS. Results: A haploblock of high linkage disequilibrium (LD) spanning PON2 and PON3 was associated with SALS. The SNPs rs10487132 and rs11981433 were in strong LD and associated with SALS in the trio (parents-affected child triad) model. The association of rs10487132 was replicated in 450 nuclear pedigrees comprising trios and discordant sibpairs. No association was found in case-control models, and their haplostructure was different from that of the trios with overall reduced LD. Resequencing identified an intronic variant (rs17876088) that differentiated between detrimental and protective SALS haplotypes. Conclusion: This study demonstrates evidence of significant association of variants in the Paraoxonase gene cluster with sporadic ALS and is compatible with the hypothesis that environmental toxicity in a susceptible host may precipitate ALS.

Background: Similarities between Alzheimer disease (AD) and Parkinson disease (PD) suggest a possible role for apolipoprotein E (APOE) in PD. Most previous studies seeking to establish such a link used case-control datasets and results have been inconsistent. Objective: To investigate APOE’s role in PD using family-based association analyses. Methods: APOE functional polymorphisms were genotyped for 658 PD affected families, including 282 multiplex and 376 singleton families. The pedigree disequilibrium test (PDT) and the genotype-PDT were used to test the risk effect of APOE. The Monks-Kaplan test was used to evaluate the effect of APOE on age at onset of PD. Results: APOE was significantly associated with risk of developing PD. Stratified analysis revealed that APOE was most strongly associated with families with a positive PD family history (global p = 0.003). Like AD, the APOE-4 allele increases disease risk while the APOE-3 allele decreases risk. We detected a positive association of APOE-3 ( p = 0.019) and a negative association of APOE-4 ( p = 0.015) with age at onset in PD. Conclusions: The APOE-4 allele increases risk and decreases age at onset of PD, an association that may not be dependent upon cognitive impairment.

Late-onset Alzheimer disease (LOAD) is the leading cause of dementia worldwide, with substantial economic and public health implications.1 LOAD is a neurodegenerative disease characterized by progressive dementia typically manifesting in the seventh to ninth decades. Neuropathological changes precede clinical symptoms by 10–20 years, resulting in clinically asymptomatic individuals carrying neuropathologic features of LOAD.2 Much of the heritability of LOAD remains unexplained, despite LOAD having a high heritability (60%–80%) and despite the identification of the APOE locus, a major genetic determinant for LOAD.3 Genetic analyses have identified more than 25 other variants associated with smaller individual effects on disease risk.4 Acknowledgment: The Alzheimer's Disease Sequencing Project (ADSP) comprises 2 Alzheimer's Disease (AD) genetics consortia and 3 National Human Genome Research Institute (NHGRI)-funded Large Scale Sequencing and Analysis Centers (LSAC). The 2 AD genetics consortia are the Alzheimer's Disease Genetics Consortium (ADGC) funded by the NIA (U01 AG032984), and the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) funded by the NIA (R01 AG033193), the National Heart, Lung, and Blood Institute (NHLBI), other NIH institutes, and other foreign governmental and nongovernmental organizations. The Discovery Phase analysis of sequence data is supported through UF1AG047133 (to G. Schellenberg, L.A. Farrer, M.A. Pericak-Vance, R. Mayeux, and J.L. Haines); U01AG049505 to S. Seshadri; U01AG049506 to E. Boerwinkle; U01AG049507 to E. Wijsman; and U01AG049508 to A. Goate. Data generation and harmonization in the Follow-up Phases is supported by U54AG052427 (to G. Schellenberg and Wang). The ADGC cohorts include Adult Changes in Thought (ACT), the Alzheimer's Disease Centers (ADC), the Chicago Health and Aging Project (CHAP), the Memory and Aging Project (MAP), Mayo Clinic (MAYO), Mayo Parkinson's Disease controls, the University of Miami, the Multi-Institutional Research in Alzheimer's Genetic Epidemiology Study (MIRAGE), the National Cell Repository for Alzheimer's Disease (NCRAD), the National Institute on Aging Late Onset Alzheimer's Disease Family Study (NIA-LOAD), the Religious Orders Study (ROS), the Texas Alzheimer's Research and Care Consortium (TARC), Vanderbilt University/Case Western Reserve University (VAN/CWRU), the Washington Heights-Inwood Columbia Aging Project (WHICAP) and the Washington University Sequencing Project (WUSP), the Columbia University Hispanic–Estudio Familiar de Influencia Genetica de Alzheimer (EFIGA), the University of Toronto (UT), and Genetic Differences (GD). The CHARGE cohorts with funding provided by 5RC2HL102419 and HL105756, include the following: the Atherosclerosis Risk in Communities (ARIC) Study which is conducted as a collaborative study supported by NHLBI contracts (HHSN268201100005C, HHSN268201100006C, HHSN268201100007C, HHSN268201100008C, HHSN268201100009C, HHSN268201100010C, HHSN268201100011C, and HHSN268201100012C), the Austrian Stroke Prevention Study (ASPS), the Cardiovascular Health Study (CHS), the Erasmus Rucphen Family Study (ERF), the Framingham Heart Study (FHS), and the Rotterdam Study (RS). The 3 LSACs are the Human Genome Sequencing Center at the Baylor College of Medicine (U54 HG003273), the Broad Institute Genome Center (U54HG003067), and the Washington University Genome Institute (U54HG003079). Biological samples and associated phenotypic data used in primary data analyses were stored at Study Investigators institutions and at the National Cell Repository for Alzheimer's Disease (NCRAD, U24AG021886) at Indiana University funded by the NIA. Associated Phenotypic Data used in primary and secondary data analyses were provided by Study Investigators, the NIA-funded Alzheimer's Disease Centers (ADCs), and the National Alzheimer's Coordinating Center (NACC, U01AG016976) and the National Institute on Aging Genetics of Alzheimer's Disease Data Storage Site (NIAGADS, U24AG041689) at the University of Pennsylvania, funded by the NIA and at the Database for Genotypes and Phenotypes (dbGaP) funded by the NIH. This research was supported in part by the Intramural Research Program of the NIH and the National Library of Medicine. Contributors to the Genetic Analysis Data included Study Investigators on projects that were individually funded by the NIA and other NIH institutes, and by private U.S. organizations, or foreign governmental or nongovernmental organizations.

Objectives: It has been suggested in some studies that head injury is a risk factor for AD, and that this risk is heightened among carriers of the APOE -e4 allele. We examined the effects of head injury and APOE genotype on AD risk in a large family study. Subjects: A total of 2,233 probands who met criteria for probable or definite AD and their 14,668 first-degree family members (4,465 parents, 7,694 siblings, and 2,509 spouses) were ascertained at 13 centers in the United States, Canada, and Germany participating in the MIRAGE (Multi-Institutional Research in Alzheimer Genetic Epidemiology) project. Information on head injury was collected by interview of multiple informants and review of medical records. Nondemented relatives and spouses served as control subjects for this study. Methods: Odds of AD for head trauma with or without loss of consciousness were computed by comparing probands with unaffected spouses using conditional logistic regression analysis. To account for the unique biologic relationship between probands and their parents and siblings, odds of AD were computed using a generalized estimating equation (GEE) Poisson regression approach. GEE logistic regression was used to examine the joint effects of APOE genotype and head injury on the odds of AD in probands and a control group comprised of unaffected siblings and spouses. Results: Comparison of probands with their unaffected spouses yielded odds ratios for AD of 9.9 (95% CI, 6.5 to 15.1) for head injury with loss of consciousness and 3.1 (2.3 to 4.0) for head injury without loss of consciousness. The corresponding odds derived from the comparison of probands with their parents and sibs were 4.0 (2.9 to 5.5) for head injury with loss of consciousness and 2.0 (1.5 to 2.7) for head injury without loss of consciousness. Head injury without loss of consciousness did not significantly increase the risk of AD in spouses (OR = 1.3; 95% CI, 0.4 to 4.1). The joint effects of head injury and APOE genotype were evaluated in a subsample of 942 probands and 327 controls (spouses and siblings). Head injury increased the odds of AD to a greater extent among those lacking e4 (OR = 3.3) than among e4 heterozygotes (OR = 1.8) or homozygotes (OR = 1.3). Conclusion: Head injury is a risk factor for AD. The magnitude of the risk is proportional to severity and heightened among first-degree relatives of AD patients. The influence of head injury on the risk of AD appears to be greater among persons lacking APOE -e4 compared with those having one or two e4 alleles, suggesting that these risk factors may have a common biologic underpinning.

To explore the impact of apoE-4 on Alzheimer's disease (AD) and its age at onset.A genetic linkage study using affected relative pairs, predominantly siblings.Three academic medical centers ascertained subjects from memory disorder clinics, nursing homes, and the local community.310 families including 679 subjects with AD by NINCDS/ADRDA and/or Khachaturian criteria and 231 unaffected subjects.ApoE genotype. ANALYTIC METHODS: Association, affected pedigree member, sibling pair, and lod score analyses.ApoE-4 was strongly associated with AD in this sample (allele frequency = 0.46 vs. 0.14 in controls, p0.000001). Results of lod score, affected pedigree member analysis, and sib-pair analysis also supported apoE-4 as a risk factor for AD. When the sample was stratified on family mean age at onset, the risk conferred by apoE-4 was most marked in the 61 to 65 age group. Individuals with two copies of apoE-4 had a significantly lower age at onset than those with one or no copies (66.4 vs. 72.0, p0.001), but individuals with one copy did not differ from those with none. Within families, the individual with the earliest age at onset had, on average, significantly more apoE-4 alleles (p0.0001) than the individual with the latest onset.This work supports previous reports of an association between apoE-4 and the development of AD and demonstrates that apoE-4 exerts its maximal effect before age 70. These findings have important implications for the potential use of apoE genotyping for diagnosis and prediction of disease. They also underscore the need to identify additional genetic factors involved in AD with onset beyond age 70 years.

Objective: To evaluate the association between the genetic variants in CACNA1C , which encodes the α1 subunit of the L-type voltage-sensitive calcium channel (LVSCC) and Parkinson disease (PD) while accounting for interactions with vitamin D concentration. Methods: Two independent case-control data sets (478 cases and 431 controls; 482 cases and 412 controls) were used. Joint effects of single nucleotide polymorphisms (SNPs) and SNP-vitamin D interaction were analyzed by comparing models containing vitamin D deficiency, SNP genotypes, SNP-vitamin D interaction, and covariates to a restricted model with only vitamin D deficiency and covariates. Meta-analysis was used to combine the joint effects in the 2 data sets. Analysis was stratified by vitamin D deficiency to demonstrate the pattern of SNP-vitamin D interaction. Results: Vitamin D deficiency was associated with PD in both data sets (odds ratio [OR] = 1.9–2.7, p ≤ 0.009). SNP rs34621387 demonstrated a significant joint effect (meta-analysis, p = 7.5 × 10 −5 ; Bonferroni corrected, p = 0.02). The G allele at rs34621387 is associated with PD in vitamin D-deficient individuals in both data sets (OR = 2.0–2.1, confidence interval = 1.3–3.5, p = 0.002) but is not associated with PD in vitamin D–nondeficient individuals ( p > 0.8 in both data sets). Conclusions: Previous studies suggest that vitamin D deficiency is associated with PD and sustained opening of LVSCC contributes to the selective vulnerability of dopaminergic neurons in PD. Our data demonstrate that the association between genetic variations in CACNA1C and PD depends on vitamin D deficiency, providing one potential mechanism underlying the association between vitamin D deficiency and PD.

Background : Genome-wide association studies, largely in research populations, have identified susceptibility single-nucleotide polymorphisms (SNPs) for a broad range of human diseases, including variants at 4q25 associated with atrial fibrillation (AF). However, no studies have evaluated the applicability of these data to practice-based settings. Methods : This study was conducted in the Vanderbilt DNA Databank, a repository that accrues 500 –900 new samples/week from routine outpatient blood draws, and included 37,335 samples as of June 2, 2008. The Databank is linked to a de-identified derivative of the electronic medial record (EMR), which includes data for the last 15 years on 1.4 million subjects. We used natural language processing techniques and billing code queries to extract AF cases and controls without AF from the first 10,000 subjects entering the Databank. Cases had AF recorded in the cardiologist report of an electrocardiogram (ECG). Controls had at least one ECG and no AF, other abnormal atrial rhythms, or atrioventricular nodal ablation in any portion of the EMR, including text documents, billing codes, and ECGs. We excluded subjects with heart transplants and non-Caucasian ethnicity. Subjects were genotyped at rs2200733 and rs10033464, both located at 4q25, previously associated with AF with odds ratios (ORs) of 1.75 and 1.42, respectively. Results : We identified 168 cases with AF and 1695 controls. The electronic algorithms had an accuracy of 98% for identifying cases and 100% for controls over a random sample of 100 subjects each. The minor allele frequencies (MAF) for rs2200733 were 0.1419 for cases and 0.1032 for controls; the MAF for rs10033464 were 0.1019 for cases and 0.908 for controls. rs2200733 was significantly associated with AF (OR [95% confidence interval], 1.44 [1.01–2.03], p=0.04). The effect of rs10033464 on AF was not significant (OR, 1.14 [0.78 –1.67], p=0.52); however, power calculations indicate that 993 cases with AF were needed to replicate this effect. Conclusion : This practice-based study replicated an association identified in research datasets between a 4q25 SNP and AF. These findings support the utility of Electronic Medical Records coupled to DNA collections as resources for genomic research.

We welcome the salient comments by Hong and colleagues pertaining to our work on cardiac sodium channel variants associated with atrial fibrillation (AF).1 We agree that besides mutations in the α-subunit of SCN5A , variants in cardiac sodium channel–related genes may also increase the risk of developing AF. Indeed, our group has recently shown that mutations in the sodium channel β-subunits are also associated with AF.2 Furthermore, recent work implicates ion channels as participants in macromolecular signaling complexes …

Objective: To identify the genetic defect causing dominant X-linked ALS and ALS/dementia, and characterize the functional and pathological determinants. Background Most cases of ALS are sporadic but about 5-10% are familial. Mutations in SOD1, TDP43 and FUS account for approximately 30% of classic familial ALS. The causes of the remaining cases of familial ALS and of the vast majority of sporadic ALS are unknown. Despite extensive studies of previously identified ALS-causing genes, the pathogenic mechanism underlying motor-neuron degeneration in ALS remains largely obscure. Dementia, usually of the frontotemporal lobar type, may occur in some ALS cases. It is unclear whether ALS and dementia share common aetiology and pathogenesis in ALS/dementia. More than a decade ago, we had linked a large ALS family to the pericentric region of the X chromosome. Design/Methods: Detailed mapping was done with dense microsatellite markers and Illumina Sentrix HumanHap300 Genotyping BeadChip. Candidate genes were sequenced using Beckman Coulter CEQ 8000 DNA analysis system. Immunohistochemistry and light and confocal microscopy were performed according to standard protocols. Neuro2a and SHSY-5Y cells were transiently co-transfected with a ubiquitin-proteasome system (UPS) reporter plasmid (Ub-G76V-GFP) and pIRES2-DsRed2 dual expression vectors containing either wildtype or mutant UBQLN2 and analyzed using a MoFlo cell sorter and Summit software. Results: We show mutations of ubiquilin2, a ubiquitin-like protein, in five families with ALS and ALS/dementia. We also show that inclusions containing ubiquilin2 are a common pathological feature in a wide spectrum of ALS and ALS/dementia. Functional studies indicate an impairment of ubiquitin-mediated proteasomal degradation in cells expressing mutant ubiquilin2. Conclusions: These data provide evidence for an impairment of protein turnover in the pathogenesis of ALS and ALS/dementia. Further elucidation of these processes may be central to the understanding of pathogenic pathways. These pathways should provide novel molecular targets for the design of rational therapies for these disorders. Supported by: The National Institute of Neurological Disorders and Stroke (NS050641), the Les Turner ALS Foundation, the Vena E. Schaff ALS Research Fund, the Harold Post Research Professorship, the Herbert and Florence C. Wenske Foundation, the David C. Asselin MD Memorial Fund, the Help America Foundation and the Les Turner ALS Foundation/Herbert C. Wenske Foundation Professorship. F.F. has support from NIH (T32 AG20506). K.A. is a postdoctoral fellow of the Blazeman Foundation for ALS. G.H.G. received travel funds from MND Scotland. Disclosure: Dr. Fecto has nothing to disclose. Dr. Deng has nothing to disclose. Dr. Chen has nothing to disclose. Dr. Hong has nothing to disclose. Dr. Boycott has nothing to disclose. Dr. Gorrie has nothing to disclose. Dr. Siddique has nothing to disclose. Dr. Yang has nothing to disclose. Dr. Shi has nothing to disclose. Dr. Zhai has nothing to disclose. Dr. Jiang has nothing to disclose. Dr. Hirano has nothing to disclose. Dr. Rampersaud has nothing to disclose. Dr. Jansen has nothing to disclose. Dr. Donkervoort has nothing to disclose. Dr. Bigio has nothing to disclose. Dr. Brooks has received personal compensation for activities with Avanir Pharmaceuticals, Bayer Healthcare Pharmaceuticals, Biogen Idec, Genentech, Inc., and Teva Neuroscience. Dr. Brooks has received research support from Avanir Pharmaceuticals, Biogen Idec, NINDS, Novartis, and Teva Neuroscience. Dr. Ajroud has nothing to disclose. Dr. Sufit has nothing to disclose. Dr. Haines has nothing to disclose. Dr. Mugnaini has nothing to disclose. Dr. Pericak-Vance has nothing to disclose. Dr. Siddique has nothing to disclose.

To identify a novel locus for ALS/FTD and its pathological correlate Amyotrophic lateral sclerosis (ALS) and Frontotemporal dementia (FTD) are both progressive fatal neurodegenerative diseases. A subset of FTD cases are linked to mutations in genes for the microtubule-associated protein tau gene and CHMPB2 respectively. In addition, mutations in the VCP are associated with inclusion body myopathy and Paget's disease where 30% of patients also have FTD. FTD is present in 5 to 10% FALS cases and may be familial. A previous FTD/ALS locus was reported to be on 9p21-22, but was not confirmed. We used 400 DNS microsatellite markers for a genome wide screening of affected relative (ARPs) pairs from …

Objectives: 1) To confirm linkage of hereditary sensory neuropathy type 1 (HSN-I) to human chromosome 9q22 in a large American family of German origin. 2) To construct a yeast artificial chromosome (YAC) contig spanning the HSN-I candidate interval. 3) To investigate the HSN-I contig for potential candidate genes. Background: HSN-I is a rare peripheral neuropathy characterized by loss of temperature sensation, ulceration and osteomyelitis of the digits, and subtle distal weakness. A gene for HSN-I has previously been mapped to human chromosome 9q22.1-q22.3 between markers D9S318 and D9S176 in an 8-cM interval in four Australian families. Methods: In a large German-American family with HSN-I, genome-wide linkage analysis was performed on 68 family members extending over five generations and including 17 affected members. Genotyping was performed with PCR, and the resulting genotypes were analyzed with two-point linkage analysis with Fastlink. A YAC contig was constructed based on the Whitehead Institute YAC contig WC9.3. Results: Two-point linkage analysis resulted in a maximum lod score of 8.2 at θ = 0 for marker D9S1815. Haplotype analysis locates the HSN-I gene between markers D9S1797 and D9S197. Using YAC clones from the Centre d’Etude du Polymorphism Humain YAC Library, we constructed a YAC contig spanning these markers. Based on the radiation hybrid map of the human genome, we estimate that the size of this interval is less than 2,500 kb. Conclusions: Our study confirms linkage of a putative HSN-I gene to chromosome 9q22, considerably narrows the HSN-I locus, and provides a basis for identification of the HSN-I gene.

Purpose. Age-related macular degeneration (AMD) is a genetically complex disorder. Tissue inhibitor of metalloproteinases-3 (TIMP3) on chromosome 22 has been identified as a gene that is mutated in Sorsby's fundus dystrophy, an autosomal-dominant macular dystrophy that phenotypically resembles AMD. The purpose of this study was to determine whether TIMP3 is a major susceptibility gene for the AMD phenotype. Methods. Thirty-eight multiplex families with AMD were identified in Massachusetts and North Carolina. The macular findings were graded according to a modification of the grading system used in the Age-Related Eye Disease Study, and persons with extensive intermediate drusen, any large drusen, geographic atrophy, or evidence of exudative maculopathy were coded as affected for the purpose of the analysis. Linkage analysis was performed using both model-dependent (lod score) and model-independent (sibpair) methods. For the lod score analysis, both autosomaldominant as well as recessive low penetrance "affecteds only" analyses were examined. Three markers, D22S280, D22S529, and D225268, linked tightly and flanking die TIMP3 locus, were chosen for die analysis. Association studies were performed by examining one randomly chosen affected person per family and comparing the patients with AMD widi a series of age, gender, and ethnically matched control subjects widi no known history of AMD. Results. Lod score analysis excluded linkage in these data for an approximately 10-cm interval surrounding the TIMP3 gene for all models tested. In addition, no significant findings were observed with either die sibpair or the association study. Conclusiom. No evidence of linkage or association or both was found between AMD and TIMP3 in these 38 families. These data suggest that although clinically similar, the genetic defect in Sorsby's fundus dystrophy is of a different cause than die majority of the genetic causes of AMD. Invest Ophthalmol Vis Sci. 1997; 38:1060-1065.