Strategies for whole-exome sequencing analysis in a case series study of familial male infertility

Background: Infertility is one of the common health issues around the world. The prevalence of male factor infertility among infertile couples is approximately 30%- 35%, of which genetic factors account for 15%. The family-based whole-exome sequencing (WES) approach can accurately detect novel variants. However, selecting an appropriate sample for data generation using WES has proven to be challenging in familial male infertility studies. The aim of this study was to identify types of pathogenic male infertility in cases of familial asthenozoospermia. Case: Two families with multiple cases were recruited for the purpose of WES. The study population included two affected cases in pedigree I and three affected cases in pedigree II. Two different variant callers (SAMtools and GATK) with a single-sample calling strategy (SSCS) and a multiple-sample calling strategy (MSCS), were applied to identify variant sites. Conclusion: In this study, we represented the results for variant prioritization of WES data without sequencing fertile siblings in the same pedigree by applying two different pipelines (homozygosity and linkage-based strategy). Using the aforementioned strategies, we prioritized annotated variants and generated a logical shortlist of private variants for each pedigree. Key words: Male infertility, Whole-exome sequencing, GATK, SAMtools.