Objective: To explore the genetic basis for 4 patients with globozoospermia.
Methods: Semen and blood samples were collected from the patients for the determination of sperm concentration, viability, survival rate, morphology and acrosome antigen CD46. Meanwhile, DNA was extracted for whole exome sequencing (WES), and candidate variants were validated by Sanger sequencing.
Results: All of the four patients were found to harbor variants of the DPY19L2 gene. Patients 1 ~ 3 had homozygous deletions of the DPY19L2 gene. Sanger sequencing confirmed that the DPY19L2 gene in patient 3 was disrupted at a recombination breakpoint area BP2, resulting in nonallelic homologous recombination and complete deletion of the DPY19L2 gene. Patients 2 and 3 respectively harbored novel homozygous deletions of exons 2 ~ 22 and exons 14 ~ 15. Patient 4 harbored heterozygous deletion of the DPY19L2 gene, in addition with a rare homozygous deletion of the 3' UTR region.
Conclusion: DPY19L2 gene variants probably underlay the globozoospermia in the four patients, which has fit an autosomal recessive pattern of inheritance and the characteristics of genomic diseases.