Phenotypic and mutational spectrum of 17 Chinese patients with Menkes Disease.

Abstract

Menkes Disease (MD) is a fatal X-linked recessive disorder caused by mutations in the ATP7A gene. Severe cases typically die before the age of three. Mild MD and occipital horn syndrome are variants of MD characterized by a less severe phenotype and longer survival. This case series aims to validate previous findings, expand the clinical phenotype, identify novel ATP7A mutations of MD patients. Observational data with follow-up were collected from 17 genetically diagnosed Chinese MD patients. All 17 patients exhibited neurological symptoms, including delayed motor milestones (100%) and seizures (58.8%). Unspecific pregnancy or delivery complications occurred in 9 patients (52.9%). The most prevalent connective tissue problems were abnormal hair (76.5%), followed by skeletal and dental abnormalities (52.9%), skin problems (41.2%) and hernia (35.3%). Sensorineural hearing loss (17.6%) was previously unreported. Coronary artery aneurysm and patent foramen ovale (5.9%) were infrequent. One 16-year-old boy carries pathological exon 3-4 deletion, presents novel mild phenotype including short stature and cerebellar ataxia. Out of 13 patients with follow-up (median: 24 months), 7 patients (53.8%) died with median survival of 40 months (range: 21-48 months), 3 patients (23.1%) show severe motor development delay and 2 (15.4%) have refractory epilepsy, only the mild MD patient shows improved cerebellar ataxia. Sixteen ATP7A mutations were identified including 6 small indels (37.5%), 5 nonsense mutations (31.2%), 2 missense mutations (12.5%), 2 exon deletions (12.5%), and 1 splice site mutation (6.25%). Fourteen mutations were novel. Our study further broadens the phenotypic and genotypic spectrums of Menkes disease.