OBJECTIVE: The purpose of this study was to evaluate the association between unexplained stillbirth (SB) and single-nucleotide polymorphisms (SNPs) in genes involved in placental function using a well-characterized cohort. STUDY DESIGN: Placentas were obtained from 50 unexplained SB and 46 live birth controls. Classification of stillbirth was by Wigglesworth criteria. SBs were stratified by weight: appropriate (AGA-SB) and small for gestational age (SGA-SB, less than the 10th percentile) and gestational age: before 32 and after 32 weeks. Placental DNA was extracted and various SNPs in the endothelial nitric oxide synthase (eNOS), Klotho, hypoxic inducible factor-1α, and and tumor necrosis factor-α genes were evaluated. RESULTS: None of the SNPs were associated with SB overall. Significantly different genotype distribution emerged for eNOS-SNP rs1800783 when comparing AGA-SB with SGA-SB and control (P = .004). Its allele-A was more frequent in AGA-SB compared with both controls (P = .03) and SGA-SB (P = .001). No differences were seen accordingly to gestational age. CONCLUSION: Unexplained stillbirth in the setting of adequate growth is associated with carrier of allele A of rs1800783 eNOS gene in the placenta.
Single-nucleotide polymorphisms in genes involved in placental function and unexplained stillbirth / Ferrari, F; Facchinetti, Fabio; Yin, H; Saade, Gr; Longo, M.. - In: AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY. - ISSN 0002-9378. - STAMPA. - 207:(2012), pp. 316.e1-7. [10.1016/j.ajog.2012.06.030]