Expanding the novel MAPKAPK5-related developmental disorder's genotype-phenotype correlation: Patient report and 19 months of follow-up

This study aimed to widen the knowledge of a recently identified, autosomal-recessive, multiple congenital anomalies syndrome to date observed in only other three children. This is the second report of biallelic mutations in MAPKAPK5 whose impairment during human development has been associated with neurological, cardiac, and facial anomalies combined with fingers and toes malformations. Through the affected patients' genetic and phenotypic features overlap, this report confirms MAPKAPK5 as causative gene and adds unique neurodevelopmental characterization. Moreover, based on the complex congenital genitourinary anomalies reported and MAPKAPK5 literature review, we also propose kidney and external genitalia involvement as a key syndromic feature whose expressivity may be more severe in males.