GNB1

Molecular characteristics

GNB1-related disorder is caused by changes in the GNB1 gene, which is found on chromosome 1.

The GNB1 gene is made out of DNA, and DNA is written in four letters: A, T, G, C. Most individuals with GNB1-related disorder have a change in only one letter in the whole GNB1  DNA sequence (for example, an A replacing a G). When this happens, the information encoded with these letters is disrupted and modified.

GNB1-related disorder is an autosomal dominant condition, meaning that only a change in one of two copies of the GNB1 gene is needed to have the disorder.

In most of the cases, the GNB1 variant found in the affected individual is not present in either parent, and is considered a “de novo” variant. In that case, the chances for future children to be affected with this condition are considered to be very low, but slightly higher than the risk for the general population. Prenatal genetic counselling can be offered in families where the diagnosis has been molecularly confirmed.