RESUMO
The underpinnings of mild to moderate neurodevelopmental delay remain elusive, often leading to late diagnosis and interventions. Here, we present data on exome and genome sequencing as well as array analysis of 13 individuals that point to pathogenic, heterozygous, mostly de novo variants in WDFY3 (significant de novo enrichment P = 0.003) as a monogenic cause of mild and non-specific neurodevelopmental delay. Nine variants were protein-truncating and four missense. Overlapping symptoms included neurodevelopmental delay, intellectual disability, macrocephaly, and psychiatric disorders (autism spectrum disorders/attention deficit hyperactivity disorder). One proband presented with an opposing phenotype of microcephaly and the only missense-variant located in the PH-domain of WDFY3. Findings of this case are supported by previously published data, demonstrating that pathogenic PH-domain variants can lead to microcephaly via canonical Wnt-pathway upregulation. In a separate study, we reported that the autophagy scaffolding protein WDFY3 is required for cerebral cortical size regulation in mice, by controlling proper division of neural progenitors. Here, we show that proliferating cortical neural progenitors of human embryonic brains highly express WDFY3, further supporting a role for this molecule in the regulation of prenatal neurogenesis. We present data on Wnt-pathway dysregulation in Wdfy3-haploinsufficient mice, which display macrocephaly and deficits in motor coordination and associative learning, recapitulating the human phenotype. Consequently, we propose that in humans WDFY3 loss-of-function variants lead to macrocephaly via downregulation of the Wnt pathway. In summary, we present WDFY3 as a novel gene linked to mild to moderate neurodevelopmental delay and intellectual disability and conclude that variants putatively causing haploinsufficiency lead to macrocephaly, while an opposing pathomechanism due to variants in the PH-domain of WDFY3 leads to microcephaly.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Relacionadas à Autofagia/genética , Encéfalo/embriologia , Encéfalo/patologia , Variação Genética/genética , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/patologia , Proteínas Adaptadoras de Transdução de Sinal/química , Adolescente , Animais , Proteínas Relacionadas à Autofagia/química , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Tamanho do Órgão , Estrutura Secundária de ProteínaRESUMO
Congenital grouped pigmentation of the retinal pigment epithelium (CGPRPE) is a rare ocular abnormality that has been described as an isolated finding or in conjunction with a few systemic conditions. We present the case of a patient with CGPRPE who also has microcephaly, intrauterine growth retardation, mild developmental delay, and deletions of 13q33.3-q34 and 11p15.4. We believe this represents a distinct syndrome in which CGPRPE and microcephaly are the predominant features and that the responsible gene possibly resides in one of the deleted chromosomal regions.
