Question: How many people are affected by Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant ?
Answer: The SBBYS variant of Ohdo syndrome is estimated to occur in fewer than 1 per million people. At least 19 cases have been reported in the medical literature.
Source: GHR

Question: What are the genetic changes related to Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant ?
Answer: The SBBYS variant of Ohdo syndrome is caused by mutations in the KAT6B gene. This gene provides instructions for making a type of enzyme called a histone acetyltransferase. These enzymes modify histones, which are structural proteins that attach (bind) to DNA and give chromosomes their shape. By adding a small molecule called an acetyl group to histones, histone acetyltransferases control the activity of certain genes. Little is known about the function of the histone acetyltransferase produced from the KAT6B gene. It appears to regulate genes that are important for early development, including development of the skeleton and nervous system. The mutations that cause the SBBYS variant of Ohdo syndrome likely prevent the production of functional histone acetyltransferase from one copy of the KAT6B gene in each cell. Studies suggest that the resulting shortage of this enzyme impairs the regulation of various genes during early development. However, it is unclear how these changes lead to the specific features of the condition.
Source: GHR

Question: What are the treatments for Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant ?
Answer: These resources address the diagnosis or management of Ohdo syndrome, SBBYS variant: - Gene Review: Gene Review: KAT6B-Related Disorders - Genetic Testing Registry: Young Simpson syndrome These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
Source: GHR