Partial trisomy/monosomy 6q in fetal cells and CVS long-term culture not present in CVS short-term culture.
A cytogenetic discrepancy in chorionic villi with implications for prenatal diagnosis is described. Chromosome analysis revealed a normal karyotype in banded metaphases from short-term culture and a chromosome count of 46 in cells of the long-term culture. After the birth of a malformed infant, a structurally aberrant chromosome 6 was found in lymphocytes and skin fibroblasts. Re-analysis of chorionic villi confirmed the result from short-term culture but disclosed the presence of the structural aberration in cells of the long-term culture. This type of inconsistency is reported for the first time and stresses the importance of a numerical and structural analysis of both short-term and long-term culture. The application of three techniques, chromosome banding, comparative genomic hybridization (CGH), and fluorescence in situ hybridization (FISH) analysis, was essential to prove that the derivative chromosome carried a combined partial trisomy/monosomy for 6q. The findings are discussed with respect to the origin of the structural aberration and to the consequences for prenatal diagnosis on chorionic villi and genetic counselling.
Wegner
R D
RD
Institute of Human Genetics, Virchow Hospital, Humboldt University Berlin, Germany.
Schröck
E
E
Obladen
M
M
Becker
R
R
Stumm
M
M
Sperling
K
K
D000328:Adult; D002478:Cells, Cultured; D015193:Chorionic Villi Sampling; D002871:Chromosome Banding; D002896:Chromosomes, Human, Pair 6; D005260:Female; D005865:Gestational Age; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D008423:Maternal Age; D009006:Monosomy; D011247:Pregnancy; D018566:Pregnancy, High-Risk; D013997:Time Factors; D014314:Trisomy