A rare genetic syndromic intellectual disability disorder with characteristics of progressive postnatal microcephaly, cerebral hypomyelination and severe psychomotor developmental delay, with absent speech, axial hypotonia, appendicular hypertonia with hyperextensibility of the wrists and ankles, hyperreflexia, severe muscle wasting and failure to thrive. Associated craniofacial dysmorphism includes triangular facies with bitemporal narrowing, down or upslanting palpebral fissures, malar hypoplasia, large malformed ears with over-folded helices, upturned bulbous nose, long smooth philtrum and thin vermilion borders.