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Renal cell carcinoma (RCC) has an undisputed genetic component and a stable 2:1 male to female sex ratio in its incidence across populations, suggesting possible sexual dimorphism in its genetic susceptibility. We conducted the first sex-specific genome-wide association analysis of RCC for men (3227 cases, 4916 controls) and women (1992 cases, 3095 controls) of European ancestry from two RCC genome-wide scans and replicated the top findings using an additional series of men (2261 cases, 5852 controls) and women (1399 cases, 1575 controls) from two independent cohorts of European origin. Our study confirmed sex-specific associations for two known RCC risk loci at 14q24.2 (DPF3) and 2p21(EPAS1). We also identified two additional suggestive male-specific loci at 6q24.3 (SAMD5, male odds ratio (OR male ) = 0.83 [95% CI = 0.78-0.89], P male  = 1.71 × 10 -8 compared with female odds ratio (OR female ) = 0.98 [95% CI = 0.90-1.07], P female  = 0.68) and 12q23.3 (intergenic, OR male  = 0.75 [95% CI = 0.68-0.83], P male  = 1.59 × 10 -8 compared with OR female  = 0.93 [95% CI = 0.82-1.06], P female  = 0.21) that attained genome-wide significance in the joint meta-analysis. Herein, we provide evidence of sex-specific associations in RCC genetic susceptibility and advocate the necessity of larger genetic and genomic studies to unravel the endogenous causes of sex bias in sexually dimorphic traits and diseases like RCC.

Background: The observation that the genetic variants identified in genome-wide association studies (GWAS) frequently lie in non-coding regions of the genome that contain cis-regulatory elements suggests that altered gene expression underlies the development of many complex traits. In order to efficiently make a comprehensive assessment of the impact of non-coding genetic variation in immune related diseases we emulated the whole-exome sequencing paradigm and developed a custom capture panel for the known DNase I hypersensitive site (DHS) in immune cells - "Immunoseq"., Results: We performed Immunoseq in 30 healthy individuals where we had existing transcriptome data from T cells. We identified a large number of novel non-coding variants in these samples. Relying on allele specific expression measurements, we also showed that our selected capture regions are enriched for functional variants that have an impact on differential allelic gene expression. The results from a replication set with 180 samples confirmed our observations., Conclusions: We show that Immunoseq is a powerful approach to detect novel rare variants in regulatory regions. We also demonstrate that these novel variants have a potential functional role in immune cells.

We have genotyped 14,436 nonsynonymous SNPs (nsSNPs) and 897 major histocompatibility complex (MHC) tag SNPs from 1,000 independent cases of ankylosing spondylitis (AS), autoimmune thyroid disease (AITD), multiple sclerosis (MS) and breast cancer (BC). Comparing these data against a common control dataset derived from 1,500 randomly selected healthy British individuals, we report initial association and independent replication in a North American sample of two new loci related to ankylosing spondylitis, ARTS1 and IL23R, and confirmation of the previously reported association of AITD with TSHR and FCRL3. These findings, enabled in part by increased statistical power resulting from the expansion of the control reference group to include individuals from the other disease groups, highlight notable new possibilities for autoimmune regulation and suggest that IL23R may be a common susceptibility factor for the major 'seronegative' diseases.

Background: DNA pooling is a technique to reduce genotyping effort while incurring only minor losses in accuracy of allele frequency estimates for single nucleotide polymorphism (SNP) markers., Results: We present an algorithm for reconstructing haplotypes (alleles for multiple SNPs on same chromosome) from pools of two individual DNAs, in which Hardy-Weinberg equilibrium conditions or other assumptions are not required. The program outputs, in addition to inferred haplotypes, a minimal number of haplotype-tagging SNPs that are identified after an exhaustive search procedure., Conclusion: Our method and algorithms lead to a significant reduction in genotyping effort, for example, in case-control disease association studies while maintaining the possibility of reconstructing haplotypes under very general conditions.

The syndrome of benign familial infantile convulsions (BFIC) is an autosomal dominant epileptic disorder that is characterized by convulsions, with onset at age 3-12 mo and a favorable outcome. BFIC had been linked to chromosome 19q, whereas the infantile convulsions and choreoathetosis (ICCA) syndrome, in which BFIC is associated with paroxysmal dyskinesias, had been linked to chromosome 16p12-q12. BFIC appears to be frequently associated with paroxysmal dyskinesias, because many additional families from diverse ethnic backgrounds have similar syndromes that have been linked to the chromosome 16 ICCA region. Moreover, one large pedigree with paroxysmal kinesigenic dyskinesias only, has also been linked to the same genomic area. This raised the possibility that families with pure BFIC may be linked to chromosome 16 as well. We identified and studied seven families with BFIC inherited as an autosomal dominant trait. Genotyping was performed with markers at chromosome 19q and 16p12-q12. Although chromosome 19q could be excluded, evidence for linkage in the ICCA region was found, with a maximum two-point LOD score of 3.32 for markers D16S3131 and SPN. This result proves that human chromosome 16p12-q12 is a major genetic locus underlying both BFIC and paroxysmal dyskinesias. The unusual phenotype displayed by one homozygous patient suggests that variability of the ICCA syndrome could be sustained by genetic modifiers.

An extensive search for in vivo immunomodulatory genes (Im genes) was made, using highly polymorphic DNA markers (microsatellites), in F2 hybrids between the two lines of mice selected for high (H) or low (L) Ab production (Biozzi mice). H and L mice have extreme phenotypes resulting from the accumulation, during selective breeding, of genes endowed with, respectively, upward or downward additive effects on Ab production. A total genome screening with 90 microsatellite markers (polymorphic between H and L mice) was conducted in 60 F2 hybrids sorted out for their extreme phenotypes from an immunized population of 240 individuals. A difference in parental marker frequency between these two groups (measured by a chi2 test) reveals the presence of an Im gene close to the marker. Significant chi2 scores were indeed found in two regions corresponding to the MHC and Igh loci, already identified as partly contributing to the H/L phenotypic difference. A notable finding was the demonstration that a gene(s), located on the proximal part of chromosome 6, was linked with Ab responsiveness. Other markers at distinct chromosomal regions also give increased chi2 scores, the two regions most clearly pointed out being on chromosomes 4 and 8.

Linkage analysis in twenty-five families with acute (type I) spinal muscular atrophy (SMA) showed that the mutant gene responsible for the disorder is tightly linked to the D5S39 locus. The mutation(s) causing the intermediate (type II) and juvenile chronic (type III) forms of SMA were also mapped to DNA marker D5S39 on chromosome 5 (5q12-q14). Thus, the three forms, which have been differentiated clinically on the basis of age of onset and clinical course, are most probably due to different mutations at a single locus on chromosome 5. Prenatal diagnosis of SMA type I will now be possible.

A clinical and epidemiological study of the Fiessinger Leroy Reiter syndrome was undertaken in Inuits from four Greenland cities, because of the frequency of HLA B27 antigen and venereal diseases in this population. A mean prevalence of 0.67 p. cent was found in Inuits from the west coast, of which 27.5 p. cent are carriers of the HLA B27 antigen. In Amassalik, on Greenland's east coast, where the frequency of B27 was estimated at 6.5 p. cent, the prevalence of the syndrome is 0.32 p. cent. Immunogenetic and preliminary familial data show that HLA B27 is present in 87.5 p. cent of the patients and that 34 p. cent have a close relative with the disease. Clinical data are comparable to those reported in the literature. Evolution is marred by frequent recurrences: 85 p. cent of the patients followed for more than ten (10) years present at least one recurrence. The total frequency of ankylosing spondylarthritis is 16.7 p. cent. It increases, in retrospect, to reach 45 p. cent in 22 patients followed for more than 15 years.