What limitation does Array CGH have regarding certain chromosomal abnormalities?

Array Comparative Genomic Hybridization (Array CGH) is a powerful genetic tool used to identify copy number variations (CNVs) across the genome. One significant limitation of Array CGH is its inability to detect balanced chromosomal rearrangements. Balanced rearrangements, such as balanced translocations or inversions, do not change the overall quantity of genetic material; therefore, they would not produce the distinct gains or losses in copy number that Array CGH is designed to identify.

This limitation is crucial in genetic counseling and diagnosis because balanced rearrangements can still have significant phenotypic implications. Patients may present with clinical features resulting from these balanced rearrangements, but since Array CGH cannot highlight them, additional testing methods would be necessary to uncover these abnormalities.

In contrast, the other choices do not accurately describe limitations of Array CGH. It does not detect all SNPs, nor does it primarily focus on SNPs; it is primarily used for detecting large deletions and duplications. While Array CGH can contribute to understanding some genetic contributions to autism spectrum disorders, it is not a diagnostic tool by itself specifically for this condition. Additionally, it can identify uniparental disomy (UPD) under certain circumstances, depending on the context and the probe