학술논문

Loss-of-Function Variants in PPP1R12A: From Isolated Sex Reversal to Holoprosencephaly Spectrum and Urogenital Malformations.
Document Type
article
Source
American Journal of Human Genetics. 106(1)
Subject
MYPT1
PPP1R12A
disorders of sex development
embryogenesis
encephalocele
facial dysmorphism
forebrain
holoprosencephaly
hypospadias
omphalocele
Abnormalities
Multiple
Adolescent
Child
Child
Preschool
Disorders of Sex Development
Female
Gestational Age
Holoprosencephaly
Humans
Male
Mutation
Myosin-Light-Chain Phosphatase
Phenotype
Pregnancy
Urogenital Abnormalities
Language
Abstract
In two independent ongoing next-generation sequencing projects for individuals with holoprosencephaly and individuals with disorders of sex development, and through international research collaboration, we identified twelve individuals with de novo loss-of-function (LoF) variants in protein phosphatase 1, regulatory subunit 12a (PPP1R12A), an important developmental gene involved in cell migration, adhesion, and morphogenesis. This gene has not been previously reported in association with human disease, and it has intolerance to LoF as illustrated by a very low observed-to-expected ratio of LoF variants in gnomAD. Of the twelve individuals, midline brain malformations were found in five, urogenital anomalies in nine, and a combination of both phenotypes in two. Other congenital anomalies identified included omphalocele, jejunal, and ileal atresia with aberrant mesenteric blood supply, and syndactyly. Six individuals had stop gain variants, five had a deletion or duplication resulting in a frameshift, and one had a canonical splice acceptor site loss. Murine and human in situ hybridization and immunostaining revealed PPP1R12A expression in the prosencephalic neural folds and protein localization in the lower urinary tract at critical periods for forebrain division and urogenital development. Based on these clinical and molecular findings, we propose the association of PPP1R12A pathogenic variants with a congenital malformations syndrome affecting the embryogenesis of the brain and genitourinary systems and including disorders of sex development.