What role does FADS1 play in fertility?

FADS1 encodes delta-5 desaturase, a key enzyme in polyunsaturated fatty acid (PUFA) metabolism, converting DGLA to arachidonic acid (AA) and EPA to DHA. AA is a precursor for prostaglandins essential for ovulation, implantation, and parturition. DHA is critical for sperm quality and fetal brain development. GWAS (e.g., rs174537) link FADS1 variants to altered PUFA levels. Observational studies suggest associations with fertility outcomes such as cycle length and sperm motility, but evidence is moderate and insufficient for personalized recommendations. Clinical relevance of single SNPs remains unclear because diet and lifestyle have larger effects. Omega-3 supplementation may be considered if deficiency is confirmed, but not based solely on FADS1 genotype. Beware of overblown marketing claims. Evidence: human-moderate.