title: The implications of detecting an extra metacentric microchromosome on amniotic fluid cell culture.
abstract: A patient was referred for amniotic fluid cell culture because of advanced maternal age. A decisional dilemma presented itself as a result of the detection of a metacentric bisatellited microchromosome (47,XX + marker) in the amniotic fluid cell culture. The decision whether to terminate the pregnancy had to be considered because the literature revealed a number of cases of an extra marker in patients with single or multiple congenital abnormalities, although other patients with a similar marker were phenotypically completely normal. The finding of an identical marker chromosome in the phenotypically normal mother and two of her off-spring favoured the continuation of the pregnancy. It would appear as if this is the first reported case in which a familial marker chromosome was detected prenatally and the pregnancy permitted to continue to term with the birth of a normal infant.
mesh_terms: D000328:Adult; D000653:Amniotic Fluid / Q000166:cytology*; D002478:Cells, Cultured; D005260:Female; D005817:Genetic Counseling; D005819:Genetic Markers; D006801:Humans; D007621:Karyotyping; D008297:Male; D010375:Pedigree; D011247:Pregnancy; D012729:Sex Chromosome Aberrations / Q000235:genetics*; D014960:X Chromosome; D014998:Y Chromosome
chemical_list: D005819:Genetic Markers