Recent advances in detecting human chromosomal abnormalities by various banding techniques.

The recent advent of banding techniques has led to the precise identification of human chromosomal abnormalities. With these techniques, the exact breakpoints in broken chromosomes are usually localized, and a phenotype-genotype correlation has been established at a very refined level for abnormalities on several chromosomes. Additionally, several so-called "new syndromes" have been recognized on the basis of cytogenetic findings. Consistent chromosomal findings have been reported in different types of neoplasia, and the prenatal diagnosis of several common cytogenetic disorders can be made through amniocentesis. The recent development of high-resolution chromosome mapping will have a dramatic impact on clinical medicine.