Association of Single Nucleotide Polymorphisms on Locus 18q21.1 in the Etiology of Nonsyndromic Cleft Lip Palate (NSCLP) in Indian Multiplex Families

Background Cleft lip palate (CLP) is a common congenital anomaly with multifactorial etiology. Many polymorphisms at different loci on multiple chromosomes were reported to be involved in its etiology. Genetic research on a single multigenerational American family reported 18q21.1 locus as a high-risk locus for nonsyndromic CLP (NSCLP). However, its association in multiple multiplex families and Indian population is not analyzed for its association in NSCLP. Aim This study was aimed to evaluate whether high-risk single nucleotide polymorphisms (SNPs) on chromosome 18q21.1 are involved in the etiology of NSCLP in multiplex Indian families. Materials and Methods Twenty multigenerational families affected by NSCLP were selected for the study after following inclusion and exclusion criteria. Genomic DNA was isolated from the affected and unaffected members of these 20 multiplex families and sent for genetic analysis. High-risk polymorphisms, such as rs6507872 and rs8091995 of CTIF, rs17715416, rs17713847 and rs183559995 of MYO5B, rs78950893 of SMAD7, rs1450425 of LOXHD1, and rs6507992 of SKA1 candidate genes on the 18q21.1 locus, were analyzed. SNP genotyping was done using the MassARRAY method. Statistical analysis of the genomic data was done by PLINK. Results Polymorphisms followed the Hardy–Weinberg equilibrium. In the allelic association, all the polymorphisms had a p-value more than 0.05. The odds ratio was not more than 1.6 for all the SNPs. Conclusion High-risk polymorphisms, such as rs6507872 and rs8091995 of CTIF, rs17715416, rs17713847 and rs183559995 of MYO5B, rs78950893 of SMAD7, rs1450425 of LOXHD1, and rs6507992 of SKA1 in the locus 18q21.1, are not associated with NSCLP in Indian multiplex families.