Factor V Leiden is associated with increased sperm count.

Study Question: Is the thrombophilia mutation factor V Leiden (FVL) associated with an increased total sperm count?

Summary Answer: Carriers of FVL have a higher total sperm count than non-FVL-carriers, which could not be explained by genetic linkage or by observations in a FVL-mouse model.

What Is Known Already: FVL has a high prevalence in Caucasians despite detrimental health effects. Carriers have been shown to have higher fecundity, which might partly explain this evolutionary paradox.

A powerful and efficient two-stage method for detecting gene-to-gene interactions in GWAS.

For over a decade functional gene-to-gene interaction (epistasis) has been suspected to be a determinant in the "missing heritability" of complex traits. However, searching for epistasis on the genome-wide scale has been challenging due to the prohibitively large number of tests which result in a serious loss of statistical power as well as computational challenges. In this article, we propose a two-stage method applicable to existing case-control data sets, which aims to lessen both of these problems by pre-assessing whether a candidate pair of genetic loci is involved in epistasis before it is actually tested for interaction with respect to a complex phenotype.

Determining the genome-wide kinship coefficient seems unhelpful in distinguishing consanguineous couples with a high versus low risk for adverse reproductive outcome.

Background: Offspring of consanguineous couples are at increased risk of congenital disorders. The risk increases as parents are more closely related. Individuals that have the same degree of relatedness according to their pedigree, show variable genomic kinship coefficients.

Resequencing three candidate genes for major depressive disorder in a Dutch cohort.

Major depressive disorder (MDD) is a psychiatric disorder, characterized by periods of low mood of more than two weeks, loss of interest in normally enjoyable activities and behavioral changes. MDD is a complex disorder and does not have a single genetic cause. In 2009 a genome wide association study (GWAS) was performed on the Dutch GAIN-MDD cohort.

Accurate prediction of a minimal region around a genetic association signal that contains the causal variant.

In recent years, genome-wide association studies have been very successful in identifying loci for complex traits. However, typically these findings involve noncoding and/or intergenic SNPs without a clear functional effect that do not directly point to a gene. Hence, the challenge is to identify the causal variant responsible for the association signal.