Genome-wide Association Study on the Relationship Between Non-syndromic Positional Plagiocephaly and Facial Asymmetry: A Case-Control Study

Positional plagiocephaly is a potential cause of facial asymmetry, with deviations sometimes involving the temporal muscles. Cranial and mandibular deviations were observed on the same side in a small subset of patients. These cases cannot be explained by the common understanding of contralateral deviation, and genetic or congenital factors are suspected. This case-control study aimed to identify novel disease-associated genes contributing to non-syndromic positional plagiocephaly and facial asymmetry using a genome-wide association study (GWAS). GWAS was performed using the PLINK software in 19 cases and 37 controls. Two single-nucleotide polymorphisms (SNPs) demonstrated p-values below the genome-wide suggestive threshold of 1 × 10⁻⁵. In patients with plagiocephaly and ipsilateral facial deviation, which cannot be attributed to positional factors (e.g., sleeping habits or temporalis muscle involvement), a potential genetic contribution involving chromosomes 3 and 15 was suggested. Herein, we present the results of a GWAS in which we identified two subtypes of diverticulum and found significant associations between the two regions. The associated SNPs were chr3:145327539 and chr15:54730212. In this study, we used a case-control GWAS to identify SNPs that showed an association between cranial deformation and facial asymmetry for the first time.