PT  - JOURNAL ARTICLE
AU  - MANUEL R. GOMEZ
AU  - ANDREW G. ENGEL
AU  - GORDON DEWALD
AU  - HAMLET A. PETERSON
TI  - Failure of inactivation of Duchenne dystrophy X‐chromosome in one of female identical twins
AID  - 10.1212/WNL.27.6.537
DP  - 1977 Jun 01
TA  - Neurology
PG  - 537--537
VI  - 27
IP  - 6
4099  - http://n.neurology.org/content/27/6/537.short
4100  - http://n.neurology.org/content/27/6/537.full
SO  - Neurology1977 Jun 01; 27
AB  - Duchenne muscular dystrophy manifested in one of girl twins. The twins were monozygous on the basis of red cell and HL antigens and skin graft compatibility. Karyotyping, including banding techniques, showed a normal number of chromosomes and a normal conflguration of the X-chromosome in both twins. The twins were identical in appearance until symptoms of Duchenne dystrophy developed in one at age-4.years. The maternal uncle had classic Duchenne dystrophy; the mother and the nonmanifesting twin showed evidence of being heterozygous for Duchenne dystrophy. The phenotypic difference in monozygous twins is readily explained by lyonization of the X-chromosome after twinning has occurred. The findings substantiate the existence of Duchenne dystrophy manifesting in females with normal karyotypes.