ASXL3 / Bainbridge-Ropers Syndrome
Bainbridge-Ropers Syndrome (BRS) is neurological spectrum disorder named in part after Dr. Matthew Bainbridge, the genetic researcher who discovered the location of ASXL3 gene and documented some of the ways mutations in the gene can affect those who have the disease. Though not everyone with an ASXL3 mutation has BRS, everyone with BRS has an ASXL3 mutation.
Bainbridge-Ropers Syndrome (BRS) stems from a heterozygous mutation in the ASXL3 gene. Located on chromosome 18, ASXL3 is one of approximately 20,000-25,000 genes that make up the human genome. The mutation in this gene that causes BRS is a truncating mutation. This means that when the body produces proteins, the mutation sends out a "stop" signal where there shouldn't be one.
First identified in 2012, BRS shares many traits of a spectrum disorder (such as Autism), which is to say that children experience a multitude of symptoms, from moderate to severe. Most children with BRS have intellectual disabilities, developmental delays, hypotonia (low muscle tone), sleep issues (difficulty falling asleep, sleep apnea), eating difficulties, mobility issues, sensory sensitivities and short attention spans. Many children fail to thrive, are nonverbal, exhibit stereotypical repetitive behaviors such as hand flapping and/or head shaking, laughing inappropriately or compulsively, and are generally fascinated by water.
"There is a tremendous opportunity to help children like Leo who are suffering from BRS. But there’s even more to consider, as 50% of the people suffering from rare genetic diseases in the world are children. By starting with the one disease closest to our hearts, we can make a difference."
— Scott Morrison, Leo’s dad
BRS children may have autism, or display traits that are characteristic of it. Beyond this, many children with BRS have similar facial characteristics: short noses with anteverted nares (nostrils end lower than the tip of the nose), high foreheads, and low set ears. Though BRS can be hereditary, BRS is usually caused by a random, spontaneous mutation, classified as a 'de novo truncating mutation’, as in Leo's case. There are no indications or warning signs during pregnancy.
Presently, there is no cure for BRS, or any other ASXL3 mutation, and equally troubling is the fact that there is very little research being done on BRS, one of the rarest of rare diseases. We believe Leo's Lighthouse can have an incredibly positive impact to create vital research opportunities.