0000000000244145
AUTHOR
Marie Ruffier-bourdet
Expanding the clinical phenotype of patients with a ZDHHC9 mutation.
In 2007, 250 families with X-linked intellectual disability (XLID) were screened for mutations in genes on the X-chromosome, and in 4 of these families, mutations in the ZDHHC9 gene were identified. The ID was either isolated or associated with a marfanoid habitus. ZDHHC9 encodes a palmitoyl transferase that catalyzes the posttranslational modification of NRAS and HRAS. Since this first description, no additional patient with a ZDHHC9 mutation has been reported in the literature. Here, we describe a large family in which we identified a novel pathogenic ZDHHC9 nonsense mutation (p.Arg298*) by parallel sequencing of all X-chromosome exons. The mutation cosegregated with the clinical phenotyp…
A new family with an SLC9A6 mutation expanding the phenotypic spectrum of Christianson syndrome
Using targeted next generation sequencing, we have identified a splicing mutation (c.526-9_526-5del) in the SLC9A6 gene in a 9-year-old boy with mild intellectual disability (ID), microcephaly, and social interaction disabilities. This intronic microdeletion leads to the skipping of exon 3 and to an in-frame deletion of 26 amino acids in the TM4 domain. It segregates with cognitive impairment or learning difficulties in other members of the family. Mutations in SLC9A6 have been reported in X-linked Christianson syndrome associating severe to profound intellectual deficiency and an Angelman-like phenotype with microcephaly, absent speech, ataxia with progressive cerebellar atrophy, ophthalmo…