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.
Department of Obstetrics and Gynecology, Nagasaki University, Graduate School of Biomedical Sciences, Sakamoto 1-7-1, Nagasaki, Japan.
Hideaki
H
Masuzaki
Kiyonori
K
Miura
Shuichiro
S
Yoshimura
Ko-Ichiro
K
Yoshiura
Tadayuki
T
Ishimaru
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*