Comprehensive investigation in patients affected by sperm macrocephaly and globozoospermia

Abstract

SUMMARYThe aim of this study was to provide a comprehensive genetic/phenotypic characterization of subjects suffering infertility owing to sperm macrocephaly (n = 3) or globozoospermia (n = 9) and to investigate whether the patients' genetic status was correlated with the alteration of various sperm parameters. AURKC was sequenced in case of sperm macrocephaly while the DPY19L2 status has been analyzed by multiple approaches including a novel qPCR-based copy number assay in case of globozoospermia. Globozoospermic patients were also analyzed for SPACA1, a novel candidate gene herein tested for the first time in humans. The effect of the patients' genetic status was interrogated by implementing the molecular screening with the characterization of several sperm parameters: (i) routine sperm analysis, integrated with transmission electron microscopy; (ii) sperm fluorescent in situ hybridization (FISH) analysis; (iii) sperm DNA fragmentation (DF) analysis. Moreover, for the first time, we performed microsatellite instability analysis as a marker of genome instability in men with sperm macrocephaly and globozoospermia. Finally, artificial reproductive technology (ART) history has been reported for those patients who underwent the treatment. Macrocephalic patients had an AURKC mutation and >89% tetraploid, highly fragmented spermatozoa. DPY19L2 was mutated in all patients with >80% globozoospermia: the two homozygous deleted men and the compound heterozygous showed the severest phenotype (90-100%). The newly developed qPCR method was fully validated and has the potential of detecting also yet undiscovered deletions. DPY19L2 status is unlikely related to FISH anomalies and DF, although globozoospermic men showed a higher disomy rate and DF compared with internal reference values. No patient was mutated for SPACA1. Our data support the general agreement on the negative correlation between macro/ globozoospermia and conventional intracytoplasmic sperm injection outcomes. Microsatellites were stable in all patients analyzed. The comprehensive picture provided on these severe phenotypes causing infertility is of relevance in the management of patients undergoing ART.

Expression profile ofPLCζ,PAWP,andTR-KITin association with fertilization potential, embryo development, and pregnancy outcomes in globozoospermic candidates for intra-cytoplasmic sperm injection and artificial oocyte activation

“…The genetic basis of globozoospermia has been a subject of extensive studies and mainly associated with deletion or deficiency of DPY19L2, SPATA16, Spaca1, and PICK1 genes which are thought to be involved in acrosome biogenesis (Elinati et al, 2012;Fujihara et al, 2012;Chianese et al, 2015;De Braekeleer et al, 2015). In this regard, assessment of RNA in spermatozoa has been recommended as it may reveal the historical record of testicular function and spermatogenesis and thereby can be considered as a genetic fingerprint of the individual.…”

Correlation between sperm ultrastructure in infertile patients with abnormal sperm morphology and DNA damage

“…However, DNA damage inside thenucleus will affect the activity of sperm. None of the patients suffering from globozoospermia had any physical issues besides infertility (Chianese et al, 2015). Patients with globozoospermia have no significant differences in sperm concentration, activity or other indexes compared to other infertile patients in routine semen examination; however, the pathogenic mechanism of globozoospermia is not clear.…”

Screening for the Homozygous C.144DELC Mutation in Aurkc Gene in Algerian Infertile Men

“…Furthermore, Chianese et al [28] screened 3 patients with macrozoospermia for c144del C mutation and found that the two macrocephalic patients with the North African origin (Moroccan) carried the c.144delC mutation. The other patient (Spanish origin), as well as his brother, were homozygous for the p.Tyr248* (c.744C>G) mutation in exon 6.…”