title: Y chromosome b2/b3 deletions and male infertility: A comprehensive meta-analysis, trial sequential analysis and systematic review.
abstract: The correlation of Y-chromosome b2/b3 partial deletions with spermatogenic failure remains dubious. We undertook a systematic review of the literature followed by meta-analyses and trial sequential analyses in order to compare the frequency of b2/b3 deletions between oligo/azoospermic infertile and normozoospermicmen. Out of twenty-four studies reviewed for meta-analysis, twenty reported no correlation between this deletion and male infertility and two studies each reported a direct and inverse correlation. In the collective analysis, 241 out of 8892 (2.71%) oligo/azoospermic individuals and 118 out of 5842 (2.02%) normozoospermic controls had a b2/b3 deletion, suggesting a relatively higher frequency of deletions in the cases. Eventually, meta-analysis showed a significant correlation between b2/b3 deletions and the risk of spermatogenic loss/infertility (Fixed model: OR=1.313, 95% CI=1.04-1.65, p=0.02; Random model: OR=1.315, 95% CI=1.02-1.70, p=0.037). Further meta-analysis on studies grouped by ethnicity and geographic regions showed that the b2/b3 deletions are significantly associated with spermatogenic loss/infertility in Mongolians, Nigro-Caucasians, East Asians and Africans, but not in Caucasians, Europeans, South Asians and Dravidians. In summary, the Y-chromosome b2/b3 deletions increase infertility risk; however, it may be significant only in the Mongolian populations and the East Asian region.
authors.affiliation: Central Drug Research Institute, Council of Scientific and Industrial Research (CSIR), Lucknow, India.
authors.forename: Sandeep Kumar
authors.initials: SK
authors.lastname: Bansal
authors.affiliation: Central Drug Research Institute, Council of Scientific and Industrial Research (CSIR), Lucknow, India.
authors.forename: Gopal
authors.initials: G
authors.lastname: Gupta
authors.affiliation: Central Drug Research Institute, Council of Scientific and Industrial Research (CSIR), Lucknow, India. Electronic address: rajender_singh@cdri.res.in.
authors.forename: Singh
authors.initials: S
authors.lastname: Rajender
mesh_terms: D016022:Case-Control Studies; D002872:Chromosome Deletion; D041322:Chromosomes, Human, Y; D005006:Ethnicity / Q000235:genetics; D006801:Humans; D007248:Infertility, Male / Q000235:genetics*; D008297:Male; D016017:Odds Ratio; D015995:Prevalence; D017594:Publication Bias; D012729:Sex Chromosome Aberrations; D058533:Sex Chromosome Disorders of Sex Development; D013091:Spermatogenesis / Q000235:genetics
keywords: Male infertility; Spermatogenic failure; Y partial deletion; b2/b3 deletion