Parental origin and mechanisms of formation of three cases of 12p tetrasomy.
Pallister-Killian syndrome is a clinically recognizable syndrome characterized by tissue-limited mosaicism for an extra 12p isochromosome. Very little is known about the underlying mechanism of this rare rearrangement. Microsatellite markers were studied from three fetuses with Pallister-Killian syndrome and their parents to determine the parent of origin and the cell division yielding the additional isochromosome. In two cases the isochromosome contained the same allele(s) as a normal transmitted chromosome 12, one paternal and one maternal in origin. A third case showed inheritance of two different maternal alleles, indicating that at least one meiotic error was involved in the ultimate formation of the extra isochromosome.
Turleau
C
C
INSERM U 383, Hôpital Necker-Enfants, Malades, Paris, France.
Simon-Bouy
B
B
Austruy
E
E
Grisard
M C
MC
Lemaire
F
F
Molina-Gomes
D
D
Siffroi
J P
JP
Boué
J
J
D000015:Abnormalities, Multiple / Q000000981:diagnostic imaging / Q000235:genetics*; D000328:Adult; D000483:Alleles; D000649:Amniocentesis; D000782:Aneuploidy; D002503:Centromere / Q000648:ultrastructure; D002881:Chromosomes, Human, Pair 12; D004276:DNA, Satellite; D005260:Female; D005333:Fetus / Q000002:abnormalities / Q000502:physiology; D005819:Genetic Markers; D006720:Homozygote; D006801:Humans; D017403:In Situ Hybridization; D007621:Karyotyping; D008297:Male; D008540:Meiosis; D008938:Mitosis; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011296:Prenatal Diagnosis; D014463:Ultrasonography
D004276:DNA, Satellite; D005819:Genetic Markers