Is type 1 diabetes (T1D) genetic or hereditary?
Researchers are still investigating what causes the onset of type 1 diabetes (T1D). While genetics and family history contribute to your predisposition to developing T1D, an external environmental trigger is also needed to initiate the disease.
There are 20-40 gene markers linked to T1D. In most cases, people with diabetes inherit these genetic risk factors from both parents. However, genes aren’t the only cause of T1D. Consider identical twins with identical genes—the American Diabetes Association reports that when one twin has T1D, the other will only contract it up to 50% of the time.
Cold weather and lack of sunshine may be a contributing factor to T1D. Cases of T1D tend to arise most often in autumn and winter. Furthermore, the incidence of T1D tends to increase in people who live farther away from the equator.
Early diet may also be related. Fewer cases of T1D arise in children who were breastfed as babies and waited until later years to eat solid foods.
Some viruses may activate T1D in someone who is susceptible. A virus that has only mild effects on most people may trigger type 1 diabetes in others.
Sources:
http://www.diabetes.org/diabetes-basics/genetics-of-diabetes.html
https://dlife.com/type-1-diabetes-genetic-hereditary-causes-treatment/
https://www.mayoclinic.org/diseases-conditions/type-1-diabetes/symptomscauses/ syc-20353011
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4038357/
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