HIVEP2 is one of over 20,000 genes found in the DNA of each person. The full gene name is Human Immunodeficiency Virus Type I Enhancer Binding Protein 2, and it is a transcription factor that binds to specific DNA sequences and controls the rate of transcription of genetic information from DNA to messenger RNA. It plays a diverse role in growth and development, and is involved in brain signaling pathways, immunity development, bone growth, and various hormone development.
We all have small variations in our genetic code - that is what makes us all unique. There may be changes in the sequence of letters in the gene message, bases can be missing (called a deletion), or bases can be added (called an insertion). Some variations in the genetic information do not seem to make any difference to the function of our cells. But some variations result in a base that differs in polarity and/or size, which may result in a loss of function in the gene. At this time, the only way to diagnose a HIVEP2 loss of function mutation is through a costly and involved genetic test called whole exome sequencing that is often not covered by insurance. The first medical paper investigating a possible connection between HIVEP2 mutations and developmental disorder was published in 2015, presenting clinical data on 3 children with mutations. A second medical paper was published in 2016, and added 6 additional children with mutations to the analysis (including Curren). After these medical publications, we have created a community with 3 additional unpublished children. Now that there are 9 published and 3 unpublished patients with HIVEP2 mutations and similar symptoms, the case is strong that loss-of-function variants in HIVEP2 are a rare cause of neurodevelopmental abnormalities.