This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Single Gene Disorders, Subject name: Pathology
CGG repeat sequence is found in 
Select and explain. 
A. Fragile X syndrome, B. Huntingtons chorea, C. Dentatorubropallidolusyian atrophy, D. Machado joseph disease
A: Fragile X syndrome
Answer: A: Fragile X syndrome 
Explanation: Expansions affecting non-coding regions Disease Protein Repeating Sequence Fragile X syndrome FMR-1 protein CGG Friedrich ataxia Frataxin GAA Myotonic Dystophy Myotonic dystrophy protein kinase (MDPK) CTG