A dermatosis characterized by thickened, hyperpigmented plaques, typically on the intertriginous surfaces and neck.

Type 2 diabetes mellitus is distinct from maturity-onset diabetes of the young (see 606391) in that it is polygenic, characterized by gene-gene and gene-environment interactions with onset in adulthood, usually at age 40 to 60 but occasionally in adolescence if a person is obese. The pedigrees are rarely multigenerational. The penetrance is variable, possibly 10 to 40% (Fajans et al., 2001). Persons with type 2 diabetes usually have an obese body habitus and manifestations of the so-called metabolic syndrome (see 605552), which is characterized by diabetes, insulin resistance, hypertension, and hypertriglyceridemia. Genetic Heterogeneity of Susceptibility to Type 2 Diabetes Susceptibility to T2D1 (601283) is conferred by variation in the calpain-10 gene (CAPN10; 605286) on chromosome 2q37. The T2D2 locus (601407) on chromosome 12q was found in a Finnish population. The T2D3 locus (603694) maps to chromosome 20. The T2D4 locus (608036) maps to chromosome 5q34-q35. Susceptibility to T2D5 (616087) is conferred by variation in the TBC1D4 gene (612465) on chromosome 13q22. A mutation has been observed in hepatocyte nuclear factor-4-alpha (HNF4A; 600281.0004) in a French family with NIDDM of late onset. Mutations in the NEUROD1 gene (601724) on chromosome 2q32 were found to cause type 2 diabetes mellitus in 2 families. Mutation in the GLUT2 glucose transporter was associated with NIDDM in 1 patient (138160.0001). Mutation in the MAPK8IP1 gene, which encodes the islet-brain-1 protein, was found in a family with type 2 diabetes in individuals in 4 successive generations (604641.0001). Polymorphism in the KCNJ11 gene (600937.0014) confers susceptibility. In French white families, Vionnet et al. (2000) found evidence for a susceptibility locus for type 2 diabetes on 3q27-qter. They confirmed the diabetes susceptibility locus on 1q21-q24 reported by Elbein et al. (1999) in whites and by Hanson et al. (1998) in Pima Indians. A mutation in the GPD2 gene (138430.0001) on chromosome 2q24.1, encoding mitochondrial glycerophosphate dehydrogenase, was found in a patient with type 2 diabetes mellitus and in his glucose-intolerant half sister. Mutations in the PAX4 gene (167413) have been identified in patients with type 2 diabetes. Triggs-Raine et al. (2002) stated that in the Oji-Cree, a gly319-to-ser change in HNF1-alpha (142410.0008) behaves as a susceptibility allele for type 2 diabetes. Mutation in the HNF1B gene (189907.0007) was found in 2 Japanese patients with typical late-onset type 2 diabetes. Mutations in the IRS1 gene (147545) have been found in patients with type 2 diabetes. A missense mutation in the AKT2 gene (164731.0001) caused autosomal dominant type 2 diabetes in 1 family. A (single-nucleotide polymorphism) SNP in the 3-prime untranslated region of the resistin gene (605565.0001) was associated with susceptibility to diabetes and to insulin resistance-related hypertension in Chinese subjects. Susceptibility to insulin resistance has been associated with polymorphism in the TCF1 (142410.0011), PPP1R3A (600917.0001), PTPN1 (176885.0001), ENPP1 (173335.0006), IRS1 (147545.0002), and EPHX2 (132811.0001) genes. The K121Q polymorphism of ENPP1 (173335.0006) is associated with susceptibility to type 2 diabetes; a haplotype defined by 3 SNPs of this gene, including K121Q, is associated with obesity, glucose intolerance, and type 2 diabetes. A SNP in the promoter region of the hepatic lipase gene (151670.0004) predicts conversion from impaired glucose tolerance to type 2 diabetes. Variants of transcription factor 7-like-2 (TCF7L2; 602228.0001), located on 10q, have also been found to confer risk of type 2 diabetes. A common sequence variant, rs10811661, on chromosome 9p21 near the CDKN2A (600160) and CDKN2B (600431) genes has been associated with risk of type 2 diabetes. Variation in the PPARG gene (601487) has been associated with risk of type 2 diabetes. A promoter polymorphism in the IL6 gene (147620) is associated with susceptibility to NIDDM. Variation in the KCNJ15 gene (602106) has been associated with T2DM in lean Asians. Variation in the SLC30A8 gene (611145) has been associated with susceptibility to T2D. Variation in the HMGA1 gene (600701.0001) is associated with an increased risk of type 2 diabetes. Mutation in the MTNR1B gene (600804) is associated with susceptibility to type 2 diabetes. Protection Against Type 2 Diabetes Mellitus Protein-truncating variants in the SLC30A8 (611145) have been associated with a reduced risk for T2D.

Abnormally increased hair growth referring to a male pattern of body hair (androgenic hair).

An increased concentration of glucose in the blood.

An increased concentration of insulin in the blood.

The presence of chronic increased pressure in the systemic arterial system.

Increased resistance towards insulin, that is, diminished effectiveness of insulin in reducing blood glucose levels.

Degenerative changes of the fat tissue.

A chronic disorder of the liver in which liver tissue becomes scarred and is partially replaced by regenerative nodules and fibrotic tissue resulting in loss of liver function.

Infrequent menses (less than 6 per year or more than 35 days between cycles).

Polycystic ovary syndrome is a condition that affects women in their child-bearing years and alters the levels of multiple hormones, resulting in problems affecting many body systems.\n\nMost women with polycystic ovary syndrome produce excess male sex hormones (androgens), a condition called hyperandrogenism. Having too much of these hormones typically leads to excessive body hair growth (hirsutism), acne, and male pattern baldness.\n\nHyperandrogenism and abnormal levels of other sex hormones prevent normal release of egg cells from the ovaries (ovulation) and regular menstrual periods, leading to difficulty conceiving a child (subfertility) or a complete inability to conceive (infertility). For those who achieve pregnancy, there is an increased risk of complications and pregnancy loss. Due to irregular and infrequent menstruation and hormone abnormalities, affected women have an increased risk of cancer of the uterine lining (endometrial cancer).\n\nIn polycystic ovary syndrome, one or both ovaries can contain multiple small, immature ovarian follicles that can appear as cysts on medical imaging. Normally, ovarian follicles contain egg cells, which are released during ovulation. In polycystic ovary syndrome, abnormal hormone levels prevent follicles from growing and maturing to release egg cells. Instead, these immature follicles accumulate in the ovaries. Affected women can have 12 or more of these follicles. The number of these follicles usually decreases with age.\n\nAbout half of all women with polycystic ovary syndrome are overweight or have obesity and are at increased risk of a fatty liver. Additionally, many women with polycystic ovary syndrome have elevated levels of insulin, which is a hormone that helps control levels of blood glucose, also called blood sugar. By age 40, about 10 percent of overweight women with polycystic ovary syndrome develop abnormally high blood glucose levels (type 2 diabetes), and up to 35 percent develop prediabetes (higher-than-normal blood glucose levels that do not reach the cutoff for diabetes). Obesity and increased insulin levels (hyperinsulinemia) further increase the production of androgens in polycystic ovary syndrome.\n\nWomen with polycystic ovary syndrome are also at increased risk for developing metabolic syndrome, which is a group of conditions that include high blood pressure (hypertension), increased belly fat, high levels of unhealthy fats and low levels of healthy fats in the blood, and high blood glucose levels. About 20 percent of affected adults experience pauses in breathing during sleep (sleep apnea). Women with polycystic ovary syndrome are more likely than women in the general popluation to have mood disorders such as depression.

Gestational diabetes is a disorder characterized by abnormally high levels of blood glucose (also called blood sugar) during pregnancy. Affected women do not have diabetes before they are pregnant, and most of these women go back to being nondiabetic soon after the baby is born. The disease has a 30 to 70 percent chance of recurring in subsequent pregnancies. Additionally, about half of women with gestational diabetes develop another form of diabetes, known as type 2 diabetes, within a few years after their pregnancy.\n\nGestational diabetes is often discovered during the second trimester of pregnancy. Most affected women have no symptoms, and the disease is discovered through routine screening at their obstetrician's office. If untreated, gestational diabetes increases the risk of pregnancy-associated high blood pressure (called preeclampsia) and early (premature) delivery of the baby.\n\nBabies of mothers with gestational diabetes tend to be large (macrosomia), which can cause complications during birth. Infants whose mothers have gestational diabetes are also more likely to develop dangerously low blood glucose levels soon after birth. Later in life, these individuals have an increased risk of developing obesity, heart disease, and type 2 diabetes.

An decreased concentration of high-density lipoprotein cholesterol in the blood.

Abnormally late or absent menarche in a female with normal secondary sexual characteristics.

An abnormally high level of uric acid in the blood.

An abnormal increase in the level of triglycerides in the blood.

A type of diabetes mellitus related not to lack of insulin but rather to lack of response to insulin on the part of the target tissues of insulin such as muscle, fat, and liver cells. This type of diabetes is typically associated with increases both in blood glucose concentrations as well as in fasting and postprandial serum insulin levels.

Loss (disappearance) of previously present subcutaneous fat tissue in arm or leg.

A condition in which superficial veins (i.e., veins just under the skin) are more conspicuous or noticable than normal.

A reduced amount of fat tissue in the lowest layer of the integument. This feature can be appreciated by a reduced skinfold thickness.

Steatosis is a term used to denote lipid accumulation within hepatocytes.

Loss (reduction of previously present) of subcutaneous adipose tissue in the gluteal region.