Shaheen syndrome is an autosomal recessive form of syndromic intellectual disability. Apart from severe intellectual disability, patients suffer from hypohidrosis, hyperkeratosis of the palms and soles, dental enamel hypoplasia and dental caries. Despite the hypohidrosis, patients are seen to have normal numbers of sweat glands. The condition can result in episodic hyperthermia. In some cases, mild microcephaly may develop. The disorder has an onset at birth.
The syndrome follows an autosomal recessive pattern of inheritance and is caused by homozygous mutations in the COG6 gene. This gene encodes a subunit of the Conserved Oligomeric Golgi complex, a hetero-octameric peripheral Golgi protein complex believed to play a role in maintaining the structure and function of the Golgi apparatus. Shaheen syndrome is believed to correlate to milder mutations in the COG6 gene such as deep intronic variants, while loss-of-function variants in the gene can cause lethal forms of CDGIIl.
