<unk>  is a X-linked dominant neurodevelopmental disorder occurring commonly in girls who undergo the phase of regression after acquiring all the developmental skills. It demonstrates variety of symptoms such as gait abnormalities, head regression, loss of speech, loss of verbal skills, problems with socialization hand-wringing movements and breathing abnormalities. Nearly 90% of cases are due to inherited mutations in  methyl-CpG-binding protein 2(MECP2) gene mutation. The other gene involved in rare cases is cyclin dependent kinase like 5(CDKL5). Being one of the most frequent causes of mental disabilities, affected children may have associated scoliosis and ambulatory problems. Girls with<unk>  are prone to gastrointestinal disorders and up to 80% have seizures.
Rett syndrome
Fragile X syndrome
Axenfeld syndrome
Krabbe disease
Foster Kennedy syndrome
Rajab-Spranger syndrome
Zellweger syndrome
Hurler-Scheie syndrome