Chromosome aneuploidy is the presence of more or less than one or even more chromosomes in a normal chromosome set.
For example, in Down syndrome, there is one extra chromosome on chromosome 21, with conditions such as mental retardation and peculiar facial features.
This is a very serious chromosomal variant that usually leads to miscarriage of the fetus.
Recently, in a study published in Science Advances, researchers from the Spanish National Cancer Research Center (CNIO) reported for the first time an exceptional case of chromosomal aneuploidy.
The patient had a rare genetic mutation, which led to the presence of chromosomal abnormalities in 30% to 40% of his blood cells, with a marked susceptibility to cancer.
This patient had 12 types of cancer over a 36-year period, five of which were malignant.
Researchers performed whole exome sequencing (WES) on the patient’s blood samples.
They found MAD1L1, a gene that is essential for cell division and proliferation.
The researchers found that the patient had mutations in both alleles of this gene (mice with this condition typically do not survive past the fetal period).
In addition, the researchers analyzed the genomic changes in peripheral blood mononuclear cells of the patient and his relatives, as well as in normal and pathological tissues and tumors of the patient.
They confirmed that the MAD1L1 mutation does cause aneuploid tumor cell formation.
However, the MAD1L1 mutation also causes upregulation of gene expression associated with inflammation in patients, leaving them in a highly inflammatory state throughout the body and possibly more likely to clear chromosomally abnormal tumor cells in vivo.
Compared to tumor markers and pathological diagnosis, studies have also shown the use of single-cell sequencing, which may help detect cancer earlier.