EFFECT OF MATERNAL AGE ON AUTOSOMAL TRISOMIES
EFFECT OF MATERNAL AGE ON AUTOSOMAL TRISOMIES
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DOI：
10.1111/j.1469-1809.1980.tb00943.x
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发表时间：
1980-01-01
影响因子：
1.9
通讯作者：
WARBURTON, D
中科院分区：
文献类型：
--
作者：
HASSOLD, T;JACOBS, P;WARBURTON, D
通过比较362例三体和790例染色体正常自然流产的数据，研究了母亲年龄对三体发生的影响。作为一个群体，三体与母亲年龄的大幅增加有关，但不同三体的影响程度存在相当大的差异。增加母体年龄的影响对于涉及小染色体的三体性最为明显，包括近端着丝粒染色体和非近端着丝粒染色体。然而，16三体是显着不同的三体的所有其他小染色体，无论是在降低的重要性，增加母亲的年龄和高频率与它发生。母亲年龄的增加对A、B、C组染色体三体性的影响不如对小染色体的影响明显。然而，有证据表明，这些染色体的三体性与母亲年龄的适度增加有关，这表明母亲年龄依赖性三体性可能是由于二价体的过早分离和由此产生的单价体的随机分离，这一过程将影响交叉数量最少的染色体，并且可能在老年女性的卵母细胞中更普遍。有人进一步提出，真正的不分离，即二价体在后期未能分离，也可能导致三体的产生。这一过程可能是独立的，或只有轻微的影响，增加母亲的年龄，但受存在的大块异染色质。
The effect of maternal age on the genesis of trisomy was studied by comparing data from 362 trisomic and 790 chromosomally normal spontaneous abortions. As a group the trisomies were associated with a substantial increase in maternal age but there were considerable differences in the magnitude of the effect for different trisomies. The effect of increasing maternal age was most pronounced for trisomies involving the small chromosomes, both acrocentric and non‐acrocentric. However, trisomy 16 was conspicuously different from trisomies for all the other small chromosomes, both in the reduced importance of increased maternal age and in the high frequency with which it occurred. The effect of increasing maternal age on trisomies for chromosomes in groups A, B and C was less clear than that for the small chromosomes. However, the evidence suggested that trisomy for these chromosomes was associated with a moderate increase in maternal age.It was suggested that the maternal age‐dependent trisomies might result from precocious disjunction of the bivalents and random segregation of the resulting univalents, a process which would affect chromosomes with the fewest number of chiasmata and which might be more prevalent in oocytes of older women. It was further suggested that true non‐disjunction, that is, the failure of bivalents to separate at anaphase, might also result in the production of trisomies. This process might be independent of, or only slightly influenced by, increasing maternal age but be affected by the presence of large blocks of heterochromatin.