Array-based molecular karyotyping (comparative genomic hybridization, aCGH) enables identification of unbalanced chromosomal rearrangements of different sizes – microdeletions and microduplication.
The molecular karyotyping developed in the late nineties and became the first tier test for detecting chromosomal imbalances in different situations in clinical practice. It has been shown that in the group of individuals with developmental delay/intellectual disability or multiple congenital anomalies or autism spectrum disorders, molecular karyotyping detects causative pathogenic genomic rearrangement in 15-20% of cases.
In the Laboratory for Molecular Cytogenetics, molecular karyotyping was introduced into regular routine practice in 2011, first into the postnatal diagnostics, and then in 2014 into the prenatal diagnostics. In addition, we use it in specific situations as a confirmatory/explanatory method after classical cytogenetic diagnostics. Oligo-based microarrays of different resolution capacities are used (Agilent).