[Chromosome microarray analysis of four fetuses with abnormal karyotypes].

Area of Science:

• Prenatal diagnosis
• Cytogenetics
• Genetics

Background:

• Karyotyping is a standard method for detecting chromosomal abnormalities.
• Complex chromosomal rearrangements can be challenging to fully characterize with conventional karyotyping.
• Prenatal diagnosis of fetal chromosomal abnormalities is crucial for genetic counseling.

Purpose of the Study:

• To evaluate the utility of chromosomal microarray analysis (CMA) in fetuses with abnormal karyotypes.
• To detect gene dosage alterations and chromosomal breakpoints in complex rearrangements.
• To assess the clinical significance of chromosomal abnormalities detected prenatally.

Main Methods:

• Amniotic fluid samples were collected for genetic analysis.
• Routine G-banded karyotyping was performed.
• Chromosomal microarray analysis (CMA) was applied to cultured amniocytes.

Main Results:

• Abnormal karyotypes were identified in the parents of 3 out of 4 fetuses.
• Parental karyotypes for the remaining fetus were normal.
• CMA revealed imbalanced chromosomal rearrangements in all 4 fetuses.

Conclusions:

• CMA is a valuable tool for characterizing complex chromosomal rearrangements.
• CMA provides a comprehensive evaluation of gene dosage and breakpoints.
• This technique enhances the diagnostic yield in prenatal cases with suspected chromosomal abnormalities.