Eleven Mutations in Six Genes Causing Abnormal Sperm Morphology: A Case Series

Objective: Infertility has become a major health problem worldwide, approximately 10%–15% of male infertility cases can be attributed to genetic mutations. However, the genetic factors contributing to male infertility remain largely unknown. This study aimed to identify genetic mutations associated with morphological abnormalities in sperm.Methods: In this study, we assessed the semen parameters of 60 patients with sperm morphological abnormalities by semen analysis, and subsequently performed targeted next-generation sequencing (NGS) to identify gene mutations. Results: Of the 60 cases of male infertility, 8 individuals (13%) were identified as carrying genetic mutations. In brief, patient 1 carried two heterozygous mutations of SUN5, including c.1066C>T and c.638delC; Patient 2 and Patient 3 had a 109.73 kb homozygous deletion on chromosome 12 in DPY19L2; patient 4 presented two heterozygous mutations (c.1670_1671delinsTT and c.255_258del) of DPY19L2; patient 5 carried a homozygous variant c.1159+1G>A of CCDC40; patient 6 had a heterozygous mutation c.38_43del in the SEPT12 gene; patient 7 had two heterozygous mutations in DNAH1 (c.10060_10061insATCT and c.12278T>C), and patient 8 presented two heterozygous mutations of CFAP43 (c.3658C>T and c.823del). Conclusions: We identified gene mutations associated with sperm morphological abnormalities in a series of male infertility cases. Eight of sixty individuals were identified as carrying gene mutations. Genetic mutations of SUN5, DPY19L2, CCDC40, SEPT12, DNAH1, and CFAP43 might be responsible for male infertility. Our study expanded the landscape of gene mutations related to sperm morphological abnormalities, which might provide new insights into the genetics underlying male infertility.