Causes of Chromosomal Abnormalities in Women

Many female friends may feel unfamiliar with female chromosomal abnormalities, because female chromosomal abnormalities are not common in our lives, and very few women will have such chromosomal abnormalities. However, female chromosomal abnormalities are very harmful to the female body, so it is still necessary to understand the causes of such symptoms as female chromosomal abnormalities.

1. Physical factors: the radiation environment in which humans live, including natural radiation and artificial radiation. Natural radiation includes cosmic radiation, earth radiation and radiation from radioactive substances in the human body. Artificial radiation includes radiation radiation and occupational exposure.

Ionizing radiation is notable for causing chromosome nondisjunction. Experiments have shown that when the oocytes of irradiated mice in the middle stage of MⅡ are compared with the oocytes of the same period that have not been irradiated, it is found that the rate of non-disjunction is significantly increased in the irradiated group, and this phenomenon is particularly obvious in older mice. When human lymphocytes were irradiated or grown in irradiated serum, the frequency of trisomy in the experimental group was found to be higher than that in the control group, and it caused chromosomal aberrations such as dicentric chromosome ectopy and deletion.

2. Chemical factors: People are exposed to various chemical substances in daily life, some of which are natural products and some are artificially synthesized. They can enter the human body through diet, breathing or skin contact, and cause chromosomal abnormalities.

3. Biological factors: When cells in culture are treated with viruses, various types of chromosomal aberrations often occur, including breakage, fragmentation, and exchange.

4. Maternal age effect: When the fetus is 6-7 months old, all oogonia have developed into primary oocytes and entered the nuclear reticulum stage from the prophase of the first meiotic division. At this time, the chromosomes are loosened and stretched again, just like the previous nucleus, and remain so until before ovulation in puberty. This state may be related to the synthesis of yolk. By puberty, due to the cyclical stimulation of oocytes by FSH, only one completes the first polar body each month. The secondary oocyte is released from the ovary and enters the fallopian tube, where it undergoes the second meiotic division and reaches metaphase. If fertilized at this time, the egg will complete the second meiotic division, become a mature egg, and combine with the sperm to form a zygote, thus starting the development of a new individual until birth. As the mother ages, under the influence of many factors inside and outside the mother, the egg may also undergo many aging changes, affecting the relationship between the same pair of chromosomes during mature division and the behavior in the late stage of division, contributing to the non-disjunction between chromosomes.

5. Genetic factors: Chromosomal abnormalities can often show a familial tendency, which suggests that chromosomal abnormalities are related to genetics.

6. Autoimmune diseases: Autoimmune diseases seem to play a role in chromosome nondisjunction. For example, there is a close correlation between increased primary thyroid autoimmune antibodies and familial chromosomal abnormalities.

The above six points are some relevant introductions about the causes of chromosomal abnormalities in women. This is a very rare phenomenon and is very harmful to women’s bodies. Therefore, female friends must pay attention to symptoms of chromosomal abnormalities, find out the causes in time, and go to the hospital for treatment in time.