A meta-GWAS (genetic-wide association search) of fertility tempo and quantum

Many industrialized societies experienced massive changes in both the postponement of age at first birth (tempo) and a drop in the total number of offspring (quantum) (Kohler, Billari & Ortega 2002; Mills et al. 2011). We carry out the first genome-wide-association-search (GWAS) meta-analysis to identify genes associated with age at first birth (AFB) and number of children ever born (NEB). GWAS represents a considerable methodological advance from previous approaches such as candidate-gene studies (Ku, Pawitan & Chia 2009). Previous research has demonstrated a genetic component to biological fecundity (Stolk et al, 2009) with twin studies estimating heritability of fertility behavior at approximately 40% (Kohler et al. 1999). Although research suggests an underlying genetic architecture of fertility behavior, the identification of genes is yet to be determined. Our meta-analysis combines GWAS findings of approximately 100,000 individuals from 52 cohorts, with preliminary results of the discovery stage completed by the IUSSP Conference.