Chromosomal studies on 2 mL of celomic fluid obtained during the fifth week of development in the timed-pregnant baboon model.

OBJECTIVE: To determine if chromosomal studies could be performed using 2 mL of celomicfluid obtained during the fifth postfertilization week in pregnant baboons. MATERIALS AND METHODS: Nine ultrasound-guided celocenteses were performed. The initial 0.5 mL of celomic fluid was discarded to decrease maternal cell contamination. Approximately 2 mL of celomic fluid was then collected. The fluid was centrifuged and the supernatant removed to a final volume of 0.5 mL. The celomic fluid sample was placed in either a small plastic flaskette chamber slide with a mix of 0.5 mL celomic fluid, 1 mL of Amniomax, and 1 mL of usedfibroblast culture medium to spread on the entire surface (n=4), or a 3.5 x 1-cm plastic Petri dish with a 24 x 30-mm glass coverslip to keep the 0.5 mL celomic fluid mixed with 1 mL of Amniomax (Invitrogen, Carlsbad, California) within a 1 cm2 area (n=5). The medium was changed on day 5 and thereafter every second to third day. The cells were harvested when the number of cells appeared sufficient for chromosomal analysis. RESULTS: Standard chromosomal studies were possible in 5 of the 9 celomicfluid samples. Mean (+/-SD) celomic fluid volume used for culture was 1.85 +/- 0.3 mL. Mean (+/-SD) time to karyotype result was 18.8 +/- 1.8 days. CONCLUSION: The findings of this study suggest that there are living cells at 36-42 days of embryonic development in the extraembryonic celomic fluid of primates and that they can be cultured for chromosomal studies. However, significant improvements in understanding the biology of cells present at 5 weeks after fertilization in celomic fluid are needed to improve culture conditions.

Prenatal diagnosis of double autosomal mosaicism (47,XX,+8/47,XX,+14): phenotype and molecular cytogenetic analysis on different tissues.

A female fetus with multiple congenital anomalies was found to have double autosomal mosaicism, 47,XX,+8/ 47,XX,+14 on chromosome analysis via amniocentesis. At delivery, the proband displayed dysmorphic features of hypertelorism, micrognathia, low set ears, cleft palate, clubfeet, omphalocele, absent gallbladder and congenital heart defects. Fluorescence in situ hybridization demonstrated a marked discrepancy in cell line populations in the tissues examined.