Cerebrotendinous xanthomatosis: recurrence of the CYP27A1 mutation p.Arg479Cys in Sardinia

Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disorder, due to mutations of the CYP27A1 gene, leading to cholestanol accumulation because of the sterol- 27-hydroxylase enzyme deficiency. Treatment with chenodeoxycholic acid (CDCA) normalizes cholestanol and improves neurophysiological findings. Several mutations of the CYP27A1 gene are described in different ethnic groups, without genotype–phenotype correlations. We describe two unrelated Sardinian families sharing the same CYP27A1 mutation.