Stability of Trisomic (47, 18+) Cells in Long-Term Mosaic Skin Fibroblast Culture

Skin fibroblasts from a subject with trisomy 18 mosaicism (47, XY, 18+) were maintained in culture over a period of 5 months. Mitotic preparations obtained after 8, 14, and 20 weeks from the time of the biopsy did not demonstrate any essential advantage of cells with one chromosomal constitution over the other. It appears that cultured skin fibroblasts are a reliable method to assess the proportion of normal and trisomic 18 cells.