A recent study shows that a little-studied eating disorder may be highly heritable.
- Avoidant Restrictive Food Intake Disorder (ARFID) is a serious eating disorder characterized by avoidance and aversion to food and eating
- A twin study shows that ARFID could be highly heritable //
- 79% of the risk of developing ARFID can be because of genes
What is Avoidant Restrictive Food Intake Disorder (ARFID)
ARFID is a serious eating disorder. The disease is characterized by an extremely limited range or amount of food consumed and resulting in persistent failure to meet nutritional and/or energy needs, ARFID is associated with considerable individual, family, and social impairment, and medical consequences can be life threatening. Researchers estimate that between one and five percent of the population is affected by the eating disorder (1✔ ✔Trusted SourceEtiology of the Broad Avoidant Restrictive Food Intake Disorder Phenotype in Swedish Twins Aged 6 to 12 Years
Go to source). Unlike other eating disorders like anorexia nervosa, ARFID is not about the patient's experience of their own body and fear of gaining weight. Alternatively, the disease is characterized by the avoidance of certain types of food due to a sensory discomfort because of the characteristics or appearance of food. This includes the fear of choking, a food poisoning phobia, or a lack of appetite.
How Genes are Linked to ARFID
Researchers have now investigated the importance of genetic factors for developing ARFID. A cohort of almost 17,000 pairs of twins in Sweden born between 1992 and 2010 participated in the study. A total of 682 children with ARFID between the ages of six and twelve years could be identified.The researchers used the twin method to determine the influence of genes and the environment on the onset of the disease.
“We know that identical twins share all genes and that fraternal twins share about half of the genes that make people different. When we then see that a certain trait is more common in both members of identical twin pairs than in fraternal twin pairs, it is an indication that there is a genetic influence. We can then estimate the degree to which a trait is influenced by genetic factors," says Lisa Dinkler, PhD, lead author of the study and a postdoctoral researcher at the Department of Medical Epidemiology and Biostatistics at Karolinska Institutet.
The Extent of Genetic Factors on ARFID
The researchers discovered that the genetic component for developing ARFID was high, 79%. This means that 79% of the risk of developing ARFID can be explained by genetic factors."This study suggests that ARFID is highly heritable. The genetic component is higher than that of other eating disorders and on par with that of neuropsychiatric disorders, such as autism and ADHD," says Lisa Dinkler.
The next step in Dr. Dinkler's research is to study the extent to which ARFID is associated with other psychiatric diagnoses, such as anxiety and depression, neurodevelopmental disorders, and gastrointestinal problems.
"We will use twin studies to test the extent to which ARFID shares underlying genetic and environmental factors with these conditions," says Dr. Dinkler.
Reference:
- Etiology of the Broad Avoidant Restrictive Food Intake Disorder Phenotype in Swedish Twins Aged 6 to 12 Years - (https://jamanetwork.com/journals/jamapsychiatry/fullarticle/2801119)
Source-Medindia