The aim of the present study was to evaluate if genetic variations in the FADS gene cluster or in the ELOVL2 gene were associated with proportions of long chain PUFAs in cord serum phospholipids or in adolescents’ serum phospholipids, and to examine any potential association between genetic variation and allergic disease at 13 years of age. The gene discussed is ELOVL2; the disease is allergic disease.