Associations Between Variations in TPH1 , TPH2 and SLC6A4 Genes and Postpartum Depression: A Study in the Jordanian Population

In this study, we investigated the association between tryptophan hydroxylase-1 (TPH1 ) (218A>C), tryptophan hydroxylase-2 ( TPH2 ) (1463G>A) and serotonin carrier family 6, member 4 (SLC6A4) [long (L) vs. short (S)] gene polymorphisms with post-partum depression (PPD) in women from Jordan. A total of 370 postpartum (130 depressed and 240 non depressed) women volunteered for the study. Genotyping was carried out using restriction fragment length polymorphism (RFLP) for TPH1 , amplification refractory mutation system (ARMS) for TPH2 and polymerase chain reaction (PCR) for SLC6A4 S and L. The Edinburgh postnatal depression scale was used to screen postpartum women. Both S and L alleles of SLC6A4 are common in Jordanian women (about 51.0 and 49.0%, respectively), while allele TPH1 -218C is more common (64.0%) than allele A (37.0%). Regarding TPH2 , allele A is absent from the examined women. None of the examined polymorphisms were found to be associated with PPD ( p >0.05). However, depression history, pregnancy problems and economic status were found to be significantly associated with PPD ( p <0.05). The results suggest that TPH1 , TPH2 and SLC6A4 S and L polymorphisms do not seem to be important in Jordan for predisposing to PPD.