Triploidy
https://rarediseases.org/rare-diseases/triploidy/
https://www.healthline.com/health/triploidy
Triploidy is the presence of an extra set of chromosomes in all of the somatic cells, giving 69 chromosomes rather than 46 per cell. Triploidy occurs when a fetus gets an extra set of chromosomes from one of the parents.
[1]. For the majority of cases, triploidy is lethal in fetuses and will lead to miscarriages, normally within the first trimester. In rare cases, some individuals survive, even to adulthood, but suffer from symptoms including: learning difficulties, hearing loss, seizures etc.[2]
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