Routine cytogenetic prenatal diagnosis using dynamic banding (RBG-GBG): a highly reproducible method for amniocytes, fetal cord blood, and chorionic villus investigations.
Dynamic banding (RBG-GBG) using pulse 5-bromodeoxyuridine (5-BrdU) incorporation during part of the last S-phase before harvesting has been used in prenatal investigations. This method has already been routinely applied in 1344 cytogenetic investigations. GBG and RBG bandings produced almost identical patterns to classical G- and R-banding methods except for heterochromatic portions and some euchromatic segments. Nevertheless, these discordances may be somewhat helpful for cytogenetic diagnosis (i.e., X numerical abnormalities). The results showed particularly good contrast and staining; 5-BrdU incorporation did not prevent additional staining. Likewise, previous RBG or GBG disclosure allowed further chromosomal identification with C-banding or nucleolar organizer staining. Simplicity and reproducibility were very helpful in cases with a low mitotic index. 5-BrdU had no significant effect on in-vitro damage because only 0.31 percent of cells were affected; so, we believe that dynamic banding should be used more extensively in cytogenetic investigations. Moreover, the staining and contrast qualities were very suitable for automatic methods of analysis now in use: i.e., metaphase finding and computer-assisted karyogram creation.
Savary
J B
JB
Service de Génétique Humaine et Pathologie Faetale, Faculté de Médecine, Lille, France.
Vasseur
F
F
Lai
J L
JL
Daudignon
A
A
Deminatti
M
M
D000649:Amniocentesis; D001973:Bromodeoxyuridine; D015193:Chorionic Villi Sampling; D002869:Chromosome Aberrations / Q000175:diagnosis*; D002871:Chromosome Banding / Q000379:methods*; D025063:Chromosome Disorders; D003936:Diagnosis, Computer-Assisted; D005260:Female; D005312:Fetal Blood / Q000166:cytology; D006801:Humans; D007621:Karyotyping; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D016196:S Phase
D001973:Bromodeoxyuridine