Medical Genetics However, birth of a live triploid is extraordinarily rare and such individuals are quite abnormal. The rare triploid that survives for more than a few hours after birth is almost certainly a mosaic, having a large proportion of diploid cellsMedical Genetics However, birth of a live triploid is extraordinarily rare and such individuals are quite abnormal. The rare triploid that survives for more than a few hours after birth is almost certainly a mosaic, having a large proportion of diploid cells