A novel homozygous truncating variant in PPFIBP1 further delineates PPFIBP1‐associated neurodevelopmental disorder

Abstract

Neurodevelopmental disorders (NDDs) are classified as a group of disorders affecting function and development of the brain and having wide clinical variability. Herein, we describe two affected individuals segregating a recessive NDD. The affected individuals exhibited phenotypes such as global developmental delay (GDD), intellectual disability (ID), microcephaly and speech delay. Wholeexome sequencing (WES) followed by bidirectional Sanger sequencing techniques identified a homozygous nonsense variant (c.466C > T; p.Gln156*) in the PPFIBP1 gene (NM_003622.4) that segregated with the disease phenotype.Further, to elucidate the effect of the variant on protein structure, 3D protein Abbreviations: GDD, global developmental delay; ID, intellectual disability; NIPT, noninvasive prenatal testing; PGTA, preimplantation genetic testing for aneuploidies; PPFIBP1, protein-tyrosine phosphatase receptor-type F polypeptide-interacting protein-binding protein 1; SAM, sterile alpha motif; WES, whole-exome sequencing.Ahmed Waqas and Romana Liaqat contributed equally.