Compound Heterozygous Mutations in SUN5 Cause Acephalic Spermatozoa: A Case Report

doi:10.12280/gjszjk.20260048

Abstract

Abstract:

Acephalic spermatozoa is a severe sperm malformation characterized by the presence of sperm without heads and detached sperm heads, and abnormal head-neck connections in the semen. Here we report a case of male infertility due to acephalic spermatozoa. Through family-based whole exome sequencing and Sanger sequencing verification, it was found that the patient has compound heterozygous mutations c.7C>T(p.Arg3Trp) and c.1043A>T(p.Asn348Ile) in the SUN5 gene. Both parents were the heterozygous carriers of these mutations. Further protein functional assays predicted that the compound heterozygous mutations in SUN5 are disruptive to protein function. These findings suggest that SUN5 mutation may be a causative factor for acephalic spermatozoa in this patient. The spouse of the patient achieved clinical pregnancy and live birth through intracytoplasmic sperm injection (ICSI) technology, indicating that ICSI is currently the most direct assisted reproductive method for such patients.

Key words: Acephalic spermatozoa, Infertility, male, Mutation, Genetic variation, Sperm injections, intracytoplasmic

CHEN Hai-xia, YANG Lin, MU Xiao-huan, SONG Xue-ru, TIAN Wen-yan, BAI Xiao-hong. Compound Heterozygous Mutations in SUN5 Cause Acephalic Spermatozoa: A Case Report[J]. Journal of International Reproductive Health/Family Planning, 2026, 45(4): 285-289.

Figures/Tables 4

References 18

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基因	染色体位置	核酸改变	氨基酸改变	转录本	外显子/内含子	杂合性	人群频率	疾病及遗传模式	致病性
SUN5	chr20:g.31571697T>A	c.1043A>T	p.Asn348Ile	NM_080675.4	EXON 13	杂合	0.000 9	16型生殖功能障碍常染色体隐性遗传	临床意义未明
SUN5	chr20:g.31592140G>A	c.7C>T	p.Arg3Trp	NM_080675.4	EXON 1	杂合	0	16型生殖功能障碍常染色体隐性遗传	临床意义未明

基因	染色体位置	核酸改变	氨基酸改变	转录本	外显子/内含子	杂合性	人群频率	疾病及遗传模式	致病性
SUN5	chr20:g.31571697T>A	c.1043A>T	p.Asn348Ile	NM_080675.4	EXON 13	杂合	0.000 9	16型生殖功能障碍常染色体隐性遗传	临床意义未明
SUN5	chr20:g.31592140G>A	c.7C>T	p.Arg3Trp	NM_080675.4	EXON 1	杂合	0	16型生殖功能障碍常染色体隐性遗传	临床意义未明