Genetic body/brain connection identified in genomic region linked to autism.
Identifying relevant genetic interactions contributing to neurodevelopmental disorders is a huge challenge facing the field. Now, a study from researchers at the Whitehead Institute identifies a direct link between deletions in two genes, namely fam57ba and doc2a, and brain-body traits, such as seizures, hyperactivity, enlarged head size, and obesity. The team state their findings point to future analyses addressing the molecular pathways by which these genes control synaptic activity and their cellular targets. The opensource study is published in the journal Human Molecular Genetics.
Previous studies show that both the fam57ba and doc2a genes reside in the 16p11.2 region of human chromosome 16. Around 4 million people worldwide, have deletions in this region which are associated with autism spectrum disorders, developmental delay, intellectual disability, seizures, and obesity. The current study demonstrates that one pair of 16p11.2 homologs can regulate both brain and body phenotypes which are reflective of those in people with 16p11.2 deletion.
The current study utilises zebrafish to uncover genotype/phenotype connections amongst 16p11.2 homologs. Results show that the genes fam57ba and doc2a in the 16p11.2 region could be key for brain development. Data findings show that fish with only one copy of each gene exhibit hyperactivity, increased propensity for seizures, increased body and head size, and fat content.
Results show that when both copies of only fam57ba are removed, the fish are much larger and fatter. The lab explain that fam57ba provides some intriguing hints as to how metabolism and brain function could be intertwined, as it produces an enzyme which plays a role in lipid production and is believed to be a metabolic regulator.
The team surmise their study shows the doc2a and fam57ba genes interact to regulate hyperactivity, seizure propensity, and control head and body size, with greater contribution from fam57ba. For the future, the researchers state their data suggest that there may be metabolic genes involved in human neurodevelopmental disorders.
Source: Whitehead Institute