###### Created: 2023-06-18 16:13 ###### Areas & Topics: #medicine ###### Note Type: #permanent ###### Connected to: [[Down's Syndrome]] [[Rett Syndrome]] [[Autism Spectrum Disorder (ASD)]] - Fragile X Syndrome is a genetic disorder caused by a trinucleotide repeat mutation of the FMR1 gene (specifically CGG). - This gene is responsible for the production of the FRMP protein which is required in brain development. - This means that individuals with Fragile X usually present with developmental delays and learning disabilities as a result of the condition. - It is an X-linked dominant condition, meaning it is typically less severe in females (as they have another X chromosome to compensate). - Fragile X is the most common monogenic cause of [[Autism Spectrum Disorder (ASD)]]. ### Clinical Features - Developmental delays - Psychomotor delays - Intellectual disabilities - Long face with prominent ears and flat feet - Macro-orchidism (abnormally large testes) ### Diagnosis - Antenatal Testing (Amniocentesis or Chronic Villus Sampling) - Genetic Testing (restriction endonuclease digestion and Southern blot analysis) ![[Fragile_X_Syndrome©SPL.jpg]] ### Resources https://www.ncbi.nlm.nih.gov/books/NBK459243/