Mutations identified in the PSAT1 gene were previously known to cause abnormalities, often severe, of the central nervous system. Beijing researchers report the original case of two unrelated patients with PSAT1 gene mutations and a particular phenotype:
- the picture associated sensitivo-motor disorders compatible with Charcot-Marie-Tooth disease (CMT) and cutaneous ichthyosis,
- CMT was clearly of axonal type,
- the first patient was homozygous for the c.43G>C variant of the PSAT1 gene while the second was composite heterozygous (combining c.43G>C and c.112A>C)
- brain imaging was strictly normal in both cases, as were blood and cerebrospinal fluid glycine and serine determinations.
The authors note a discrete improvement of the cutaneous signs after oral administration of serine.
