Three patients with ring (X) chromosomes and a severe phenotype.

TitleThree patients with ring (X) chromosomes and a severe phenotype.
Publication TypeJournal Article
Year of Publication1993
AuthorsDennis NR, Collins AL, Crolla JA, Cockwell AE, Fisher AM, Jacobs PA
JournalJournal of medical genetics
Date Published1993 Jun

Three patients with mosaicism and a cell line containing a small ring (X) chromosomei are described. Their phenotypei is similar to several previously reported patients with a 45,X/46,X,r(X) karyotypei and a phenotype far more severely affected than expected in Turner's syndrome. The clinical picture includes mental retardation, a facial appearance reminiscent of the Kabuki make up syndrome, and limb anomalies. Some of the patients also had streaky hyperpigmentation of the skin in a pattern suggesting dermali mosaicism. It has been hypothesised that the severe phenotype might be the result of the small r(X) chromosome remaining active. However, there is little critical evidence to support this suggestion, while there is considerable evidence against it, including (1) a similar phenotype in 45,X/46,X,r(Y) patients, (2) the late replication of some of the small r(X) chromosomes associated with this phenotype, and (3) the expression of XIST in some of the affected patients.

Alternate JournalJ. Med. Genet.
Citation Key8326492