People having unusual sets of chromosomes often show mental deficits. They are aneuploidies.
Aneuploidies refer to an abnormal number of chromosomes in offspring due to problems during meiosis.
Aneuploidies in different chromosomes may lead to different disease-health conditions.
Aneuploidies are often associated with mental deficits because this trait is highly dependent on gene expression balance.
Learn more about aneuploidies here:
https://brainly.com/question/2130641