A monozygotic twin pregnancy discordant for acardia and X-inactivation pattern.
Monochorionic, diamniotic twins discordant for acardia are reported. A 775 g acardius was dead, generally hydropic and severely malformed, while the other twin with a weight of 1314 g was phenotypically normal. Both twins had a normal 46 XX karyotype. Genotyping at 24 autosomal polymorphic loci revealed that the twins were identical (monozygotic) and ruled out uniparental disomy for chromosome 2. X-inactivation studies showed a skewed pattern in the acardiac twin and a normal random pattern in the co-twin, suggesting that the underdevelopment of the acardiac twin may have reflected the small number of original cells that were separated from the inner cell mass.
Masuzaki
Hideaki
H
Department of Obstetrics and Gynecology, Nagasaki University, Graduate School of Biomedical Sciences, Sakamoto 1-7-1, Nagasaki, Japan.
Miura
Kiyonori
K
Yoshimura
Shuichiro
S
Yoshiura
Ko-Ichiro
K
Ishimaru
Tadayuki
T
D000015:Abnormalities, Multiple / Q000235:genetics*; D000328:Adult; D002869:Chromosome Aberrations; D004200:Diseases in Twins / Q000235:genetics*; D004303:Dosage Compensation, Genetic; D005260:Female; D006330:Heart Defects, Congenital / Q000235:genetics*; D006801:Humans; D007621:Karyotyping; D011247:Pregnancy; D014430:Twins, Monozygotic / Q000235:genetics*