How are APOE and Fruchtbarkeit related?

APOE variants (especially ε4) are linked to altered lipid metabolism, which could theoretically affect fertility – e.g., via cholesterol availability for steroid hormones or sperm quality. However, evidence is moderate, coming from smaller studies; large GWAS or clinical guidelines are lacking. APOE is primarily known for Alzheimer's and cardiovascular risk. A DNA test cannot reliably predict fertility. Lifestyle, hormonal status, and other genes play a much larger role. Beware of overinterpreted marketing claims.