Evaluation of mutations in DHCR7 gene in high-risk pregnant women for Smith Lemli Opitz Syndrome during second-trimester screening in Nasiriyah

Abstract

Introduction: Smith Lemli Opitz Syndrome (SLOS) is the second most frequent metabolic disease in various populations. At the end of the cholesterol production pathway, a mutation in the dehydrocholesterol reductase (DHCR7) gene causes SLOS. DHCR7 is a membrane protein that needs the cofactor NADPH to function. In SLOS patients, more than 130 distinct DHCR7 mutations have been discovered. The impact of the DHCR7 gene mutation on the severity and symptoms of SLOS in patients, particularly high-risk pregnant women, has been recommended.
 Methods: This study was performed on 20 high-risk pregnant women with SLOS at a second-trimester screening in the Nasiriyah. To detect DHCR7 gene mutations in infected individuals, DNA was collected from peripheral blood, and Sanger sequencing was performed.
 Result: 20 women suspected of having SLOS with 26.7 ±8.01 years old (SD) were included. 70% (14) of families had a history of having a child with SLOS disorder. In contrast, the 30 % (6) remaining families had never had SLOS before and were discovered during pregnancy. Only 4 pregnant women (20%) identified with DHCR7 mutation. The DHCR7 gene was analyzed from exons 1 to 9, and a c.445C> T (CAA-TAA) mutation was detected in exon 6 of this gene.
 Conclusion: According to the findings of prior studies and the present study, the sequencing of the DHCR7 gene can detect around 96 percent of known variations and pathogens; therefore, the identification and analysis of the DHCR7 gene during pregnancy and screening for SLOS may be claimed to be beneficial.