Genetic factors play a role in the etiology of childhood and adolescent leukemia, although the vast majority is due to acquired factors.
Abnormalities in certain chromosomes and genes due to hereditary causes can greatly increase the chance of developing certain tumors, called hereditary tumor syndromes, which are divided into two categories: autosomal dominant and autosomal recessive.
Patients with certain hereditary tumor syndromes are significantly more likely than normal to have leukemia, for example:
- trisomy 21
- Fanconi anemia
- Familial myelodysplastic syndrome/acute myeloid leukemia due to mutations/deletions in the GATA2 gene
- Bloom syndrome
- Li-Fraumeni syndrome
- Ataxia capillaris
- Congenital dyskeratosis et al
So, if the parents do not carry the abnormal chromosomes/genes described above and the child with leukemia in the first child does not have hereditary tumor syndrome detected, the probability of leukemia in the second child should be equal to that of the general population.
And if unfortunately there is an inherited chromosomal/genetic problem of the aforementioned parents or the first-born child, the second child is highly likely to have the same inherited neoplastic syndrome with a much higher risk of developing leukemia.