Which syndrome is X-linked, typically affecting males, and is characterized by macro-orchidism, hand stereotypies, and sometimes autistic features?

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Multiple Choice

Which syndrome is X-linked, typically affecting males, and is characterized by macro-orchidism, hand stereotypies, and sometimes autistic features?

Fragile X syndrome is an X-linked disorder that typically affects males and is characterized by macroorchidism, hand stereotypies (such as hand-flapping), and often autistic features. The genetic basis is a CGG trinucleotide repeat expansion in the FMR1 gene on the X chromosome, which silences the gene and reduces the FMRP protein essential for normal synaptic function. Because males have only one X, the impact is usually more pronounced, while females can be carriers with milder symptoms due to X-inactivation variability. Macroorchidism tends to become evident after puberty, and autism-like features can be prominent in many affected individuals. Rett syndrome is mainly seen in females with regression and hand-wringing but not macroorchidism; Williams syndrome involves a 7q11.23 deletion and is not X-linked; Angelman syndrome arises from maternal imprinting issues on chromosome 15 and has its own distinct features.

Fragile X syndrome is an X-linked disorder that typically affects males and is characterized by macroorchidism, hand stereotypies (such as hand-flapping), and often autistic features. The genetic basis is a CGG trinucleotide repeat expansion in the FMR1 gene on the X chromosome, which silences the gene and reduces the FMRP protein essential for normal synaptic function. Because males have only one X, the impact is usually more pronounced, while females can be carriers with milder symptoms due to X-inactivation variability. Macroorchidism tends to become evident after puberty, and autism-like features can be prominent in many affected individuals. Rett syndrome is mainly seen in females with regression and hand-wringing but not macroorchidism; Williams syndrome involves a 7q11.23 deletion and is not X-linked; Angelman syndrome arises from maternal imprinting issues on chromosome 15 and has its own distinct features.

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