Which is a limitation of PGT?

• A. It guarantees a healthy baby
• B. Mosaicism can lead to false results
• C. It is available everywhere at no cost
• D. It requires no specialized lab facilities

Answer: (B)

Preimplantation Genetic Testing aims to screen embryos for chromosomal abnormalities or specific gene mutations before IVF transfer. A key limitation is mosaicism: the embryo can contain a mix of normal and abnormal cells. Since only a few cells are biopsied, those cells may not reflect the genetic status of the entire embryo. This can lead to false results, such as labeling an embryo as normal when abnormal cells exist, or discarding an embryo that could develop normally. Mosaicism varies between embryos and can complicate interpretation, so PGT cannot guarantee a healthy baby.

Other statements don’t fit as limitations: PGT does not guarantee a healthy baby, it is not universally available at no cost, and it requires specialized lab facilities and trained personnel to perform the biopsy and genetic analysis.