Gene involved in rett syndrome-
**Core Concept**
Rett syndrome is a rare genetic disorder that affects brain development and is characterized by severe intellectual disability, loss of speech, and physical abnormalities. It is caused by a mutation in a specific gene that plays a crucial role in brain development.
**Why the Correct Answer is Right**
Rett syndrome is caused by a mutation in the MECP2 gene, which encodes a protein that regulates gene expression in neurons. The MECP2 protein binds to methylated DNA and represses the expression of genes involved in neuronal development and function. Mutations in MECP2 disrupt this regulation, leading to the characteristic features of Rett syndrome. The MECP2 gene is located on the X chromosome, which is why Rett syndrome predominantly affects females.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify a gene that is associated with Rett syndrome.
**Option B:** This option is incorrect because it is actually the gene responsible for Fragile X syndrome, a different genetic disorder that affects brain development.
**Option C:** This option is incorrect because it is not a known gene associated with Rett syndrome.
**Clinical Pearl / High-Yield Fact**
Rett syndrome is an X-linked dominant disorder, meaning that a single copy of the mutated MECP2 gene is sufficient to cause the condition. This is why males with Rett syndrome are more severely affected than females, who may have milder symptoms due to X-chromosome inactivation.
**Correct Answer: D. MECP2**