FISH chromosome analysis

Fluorescent in-situ hybridization (FISH) makes it possible to detect chromosomal diseases such as Down's syndrome (trisomy 21) or Klinefelter's syndrome (extra X chromosome).

In the first example, a healthy male embryo is observed, with 2 copies of chromosome 21 and one copy for each of the sex chromosomes (XY). Secondly, the embryo has 3 copies of chromosome 21, resulting in a child with Down syndrome. Finally, the embryo is also male, but with an extra X chromosome, which means that the future baby will have Klinefelter's syndrome.