Leptin and Leptin Receptor Polymorphisms in Infants and Their Parents: Correlation with Preterm Birth

It has been proven that single-nucleotide polymorphisms (SNPs) in LEP and LEPR genes could predispose individuals to an increased risk of pregnancy adverse outcomes (PAOs) such as recurrent pregnancy loss (RPL) and pre-eclampsia. Preterm birth (PTB) is the leading cause of infant mortality. We decided to investigate the correlation between PTB and LEP and LEPR SNPs. The study cohort included families who underwent spontaneous PTB and control samples of families who had at-term-born (≥37 weeks of gestational age) children. Swabs were performed by rubbing the sticky end for about 30 s on the gum and on the inside of the cheek, allowing us to collect the flaking cells of the oral mucosa. Genotyping of the three SNPs-LEPRA668G, LEPG2548A and A19G-was carried out via an ARMS-MAMA real-time PCR procedure, as previously described. Regarding LEPG2548A, we found that the most expressed genotype in infants both in the preterm and the at-term group was AG; however, we did not discover any statistically significant difference (p = 0.97). Considering LEPA19G, none among the infants and parents were found to carry the AA genotype. No statistically significant differences were found between children, mothers and fathers belonging to preterm and at-term groups. We did not find a statistically significant association in newborns and their mother, but our results show a statistical correlation with the LEPRA668G genotype GG of the father. This fact can contribute to defining genetic risk factors for PTB. Further studies are certainly needed to better clarify the role of genetics in influencing preterm delivery.