: 501

Adults
Recognised effects include:
Increased 5-alpha-reductase
Reduced sex hormone-binding globulin (SHBG)
Reduced muscle mass and strength
Baldness in men
Reduced bone mass and osteoporosis (Decreased bone density)
Reduced energy
Impaired concentration and memory loss
Increased body fat, particularly around the waistline
Lipid abnormalities, particularly raised LDL cholesterol
Increased levels of fibrinogen and plasminogen activator inhibitor
Cardiac dysfunction, including a thickened intima media
Lack of well-being
Depression and anxiety
Social isolation
Fibromyalgia syndrome
Neuromuscular dysfunction
Central adiposity
Decreased muscle mass
Insulin resistance
Accelerated atherogenesis
Prothrombotic state
Decreased sweating and thermoregulation. Causes
Growth hormone deficiency in childhood commonly has no identifiable cause (idiopathic), and adult-onset GHD is commonly due to pituitary tumours and their treatment or to cranial irradiation. A more complete list of causes includes:

mutations of specific genes (e.g., GHRHR, GH1)
congenital diseases such as Prader-Willi syndrome, Turner syndrome, or short-stature homeobox gene deficiency
congenital malformations involving the pituitary (e.g., septo-optic dysplasia, posterior pituitary ectopia)
chronic kidney disease
intracranial tumors in or near the sella turcica, especially craniopharyngioma
damage to the pituitary from radiation therapy to the head (e.g. for leukemia or brain tumors), from surgery, from trauma, or from intracranial disease (e.g. hydrocephalus)
autoimmune inflammation (hypophysitis)
ischemic or hemorrhagic infarction from low blood pressure (Sheehan syndrome) or hemorrhage pituitary apoplexyThere are a variety of rare diseases that resemble GH deficiency, including the childhood growth failure, facial appearance, delayed bone age, and low insulin-like growth factor-1 (IGF-1) levels. However, GH testing elicits normal or high levels of GH in the blood, demonstrating that the problem is not due to a deficiency of GH but rather to a reduced sensitivity to its action.
Anticipation tends to be less severe than in cases of maternal inheritance.The RNA from the expanded trinucleotide repeat region forms intranucleoplasmic hairpin loops due to the extensive hydrogen bonding between C-G base pairs, and it has been demonstrated that these sequester the splicing regulator MBNL1 to form distinctive foci.A severe form of DM1, congenital myotonic dystrophy, may appear in newborns of mothers who have DM. Congenital myotonic dystrophy can also be inherited via the paternal gene, although it is said to be relatively rare. Congenital means that the condition is present from birth. DM2
The microsatellite expansion responsible for DM2 is of cytosine-cytosine-thymine-guanine (CCTG) repeats, classifying it as a tetranucleotide repeat disorder. This expansion occurs in the first intron CNBP gene on chromosome 3.The repeat expansion for DM2 is much larger than for DM1, ranging from 75 to over 11,000 repeats. Like DM1, the size of the microsatellite repeat array lengthens from generation to generation. Unlike DM1, anticipation does not result, as the degree of repeat expansion beyond 75 repeats does not affect the age of onset or disease severity.The repeat expansion produces an RNA transcript that binds to RNA-binding proteins such as MBNL1, as in DM1. Also, repeat expansion likely reduces expression of CNBP, loss of which causes muscle toxicity. Pathophysiology
Molecular
Mutations of DM1 and DM2 cause production of RNA that sequesters RNA-binding proteins, causing dysregulated RNA splicing. This dysregulated RNA splicing is particularly toxic to skeletal, cardiac, and smooth muscle. One example in DM1 involves the chloride channel ClC-1.