Miscarriages are often associated with genetic abnormalities, z. About 50-60% of all first trimester miscarriages are caused by such abnormalities, and the risk increases with the age of the mother. Here are some of the genetic causes of miscarriage:
Aneuploidy: It is a condition in which a cell has an abnormal number of chromosomes. The most common example of aneuploidy is Down's syndrome, in which there is an extra chromosome 21. Aneuploidy is the most common genetic cause of miscarriage.
Balanced translocations: Balanced translocations occur when chromosome fragments swap places, but all genetic information is still present. People with a balanced translocation often have no symptoms, but may have a higher risk of miscarriage or having children with an unbalanced translocation, which can lead to malformations or genetic diseases.
Chromosome structure abnormalities: Sometimes chromosomes can have extra or missing fragments, which can lead to developmental abnormalities and cause miscarriage.
Monogenic mutations: Specific gene mutations can lead to recurrent miscarriages. An example is the MTHFR gene mutation, which is associated with an increased risk of thrombosis and miscarriage, There are currently over 270 genes known in which mutations are associated with recurrent miscarriage.
Trinucleotide repeats: Some genetic diseases, such as Fragile X syndrome, are caused by repeats of three nucleotide sequences. These diseases can sometimes lead to miscarriages.
Genetic diagnostic tests, such as tests for chromosome aneuploidy, tests for chromosome translocations or next-generation sequencing (NGS) including whole-exome sequencing (WES), are of great importance in identifying the genetic causes of miscarriages.
