Identification of sex chromosome by fluorescence in situ hybridization.

Fluorescence in situ hybridization (FISH) is the complicated and very effective technique to determine the origin of chromosome material that cannot be identified by conventional banding techniques. Also determining the hidden sex chromosome and the percentage of mosaicism. Five peripheral blood and one cord blood sample were used to perform centromeric X and Y chromosome-specific DNA probe to determine the sex chromosome. Comparing the percentage of mosaicism between conventional cytogenetic technique and FISH technique, we found a different ratio in mosaicism. That is because the molecular cytogenetic study was the evaluation of chromosome identification in both dividing (metaphase) and non-dividing cells (interphase nuclei).