Which of the following hormones are raised in PraderWilli syndrome?
**Core Concept**
Prader-Willi syndrome (PWS) is a genetic disorder characterized by hypotonia, obesity, and intellectual disability. It is caused by a deletion or mutation of genes on chromosome 15 inherited from the father. Hormonal imbalances, particularly related to growth hormone and sex hormones, play a crucial role in the clinical presentation of PWS.
**Why the Correct Answer is Right**
In PWS, there is a deficiency of growth hormone and gonadotropin-releasing hormone (GnRH). This deficiency leads to low levels of growth hormone, insulin-like growth factor 1 (IGF-1), luteinizing hormone (LH), and follicle-stimulating hormone (FSH). However, the levels of sex hormones such as testosterone and estrogen are elevated due to the lack of negative feedback from GnRH and gonadotropins. This hormonal imbalance contributes to the clinical features of PWS, including short stature, hypogonadism, and obesity.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not relevant to the hormonal changes seen in Prader-Willi syndrome.
**Option B:** Growth hormone levels are actually decreased in PWS, not increased.
**Option C:** IGF-1 levels are also decreased in PWS due to the deficiency of growth hormone.
**Clinical Pearl / High-Yield Fact**
It is essential to recognize the hormonal imbalances in PWS, as they contribute to the clinical features of the disorder. Growth hormone therapy is often used to treat the growth hormone deficiency and improve the height and body composition of individuals with PWS.
**Correct Answer: C. Growth hormone levels are actually decreased in PWS, not increased.