New Insights into Male Fertility: AK9 Gene Linked to Sperm Motility
A team of researchers from Xiamen University in China has identified a gene that plays a pivotal role in male fertility. In their investigation, the AK9 protein, when mutated, is linked to reduced sperm motility, a condition known as asthenozoospermia. The finding aligns with reports from NewsMedical and adds a genetic dimension to the understanding of this common fertility challenge.
The study enrolled 165 Chinese men diagnosed with asthenozoospermia and compared them with 200 healthy volunteers. Asthenozoospermia refers to a seminal fluid abnormality marked by a lower proportion of motile sperm. While genetic factors can contribute, lifestyle and environmental influences such as alcohol consumption, nicotine use, stress, and immune health also affect sperm movement. This broader context helps explain why motility issues arise in some individuals even when routine semen parameters appear normal on standard tests.
Initial analyses examined the seminal fluid of both men with asthenozoospermia and healthy controls. Physically, the samples showed little difference across several standard parameters. Yet deeper molecular analysis revealed that the AK9 mutation alters the three-dimensional structure of the enzyme, compromising the energy balance and mobility of sperm cells. The altered conformation appears to hinder the flagellar motion essential for successful fertilization, providing a plausible mechanism for reduced motility. Researchers also noted that the mutation seems inherited in some families, as sample data indicated close genetic relationships among affected individuals, including two blood relatives with asthenozoospermia.
These results reinforce the notion that genetic variation can influence male fertility and that specific protein changes may disrupt sperm function at a fundamental level. The work from Xiamen University contributes to a growing body of evidence that links genetic mutations with reproductive outcomes, underscoring the importance of genetic screening and counseling in cases of unexplained infertility. While this discovery is a meaningful step forward, scientists emphasize the need for broader studies to determine how common AK9-related changes are across diverse populations and to explore possible interventions that could mitigate the impact on sperm motility. In the meantime, clinicians advocate a comprehensive approach that considers both genetic and lifestyle factors when assessing male fertility risks.
Experts caution that more research is required to translate these findings into routine clinical practice. Nonetheless, the study highlights how advances in genetic analysis are widening the understanding of male reproductive health and may eventually lead to targeted strategies for diagnosis and treatment.