Familial translocations involving 15q11-q13 can give rise to interstitial deletions causing Prader-Willi or Angelman syndrome.
A de novo interstitial deletion of 15q11-q13 is the major cause of Prader-Willi syndrome (PWS) and Angelman syndrome (AS). Here we describe two unrelated PWS patients with a typical deletion, whose fathers have a balanced translocation involving the PWS/AS region. Microsatellite data suggest that the deletion is the result of an unequal crossover between the derivative chromosome 15 and the normal chromosome 15. We conclude that familial translocations involving 15q11-q13 can give rise to interstitial deletions causing PWS or AS and that prenatal diagnosis in such families should include fluorescence in situ hybridisation or microsatellite studies or both.
Horsthemke
B
B
Institut für Humangenetik, Universitätsklinikum Essen, Germany.
Maat-Kievit
A
A
Sleegers
E
E
van den Ouweland
A
A
Buiting
K
K
Lich
C
C
Mollevanger
P
P
Beverstock
G
G
Gillessen-Kaesbach
G
G
Schwanitz
G
G
D017204:Angelman Syndrome / Q000235:genetics*; D002884:Chromosomes, Human, Pair 15; D005260:Female; D017353:Gene Deletion; D006801:Humans; D008297:Male; D010375:Pedigree; D011218:Prader-Willi Syndrome / Q000235:genetics*; D014178:Translocation, Genetic