2018, Number 4
Mechanisms related to the origin of human aneuploidies in advanced maternal age
de la Torre SME, Herrera MM
Full text
Language: Spanish
References: 0
Page: 359-363
PDF size: 250.05 Kb.
ABSTRACT
Female fertility is restricted from the age of 35 due to the limited reserve of oocytes and the increase of chromosomal aberrations, mainly aneuploidies. Premature separation of sister chromatids, non-disjunction in meiosis I or II and reverse segregation are the most common errors in meiotic segregation. In older women these errors are explained by the deterioration in cohesion between homologous chromosomes and sister chromatids, although aberrant recombination, shortening of telomeres and microcirculatory alterations around the follicle have been also related. In young women aneuploidies are due to the instability of the spindle and the formation of multipolar spindles. The effect of advanced maternal age is not limited to meiosis; errors in mitotic divisions after fertilization, and increased mitochondrial DNA are also linked to aneuploidies.