Table 3.
Comparison of phenotypic features of monogenic forms of obesity
| Gene | Obesity | Birth weight | Endocrine abnormalities | Hyperphagia | Inheritance | Chromosome |
|---|---|---|---|---|---|---|
| LEP | Severe | Normal | Low
leptin Hypogonadism High thyroid stimulating hormone High insulin |
+ | Recessive | 7q31.3 |
| LEPR | Severe | ? |
High
leptin Pituitary dysfunction Hypogonadotrophic hypogonadism Hypothalamic hypothyroidism Sympathetic dysfunction High insulin |
+ | Recessive | 1p31 |
| POMC | Severe | Normal | Red hair pigmentation ACTH deficiency, hypocortisolism Low α-MSH |
+ | Recessive | 2p23.3 |
| PC1 | Severe | ? | Hypogonadotrophic
hypogonadism Hypocortisolism High proinsulin, low insulin Postprandial hypoglycemia High POMC |
? | Recessive | 5q1.5–2.1 |
| MC4-R | Severe | Normal | Not observed | + | Dominant | 18q22 |
| NROB2 | Mild | High | Mild hyperinsulinemia | − | Dominant | 1p36.1 |
LEP, leptin; LEPR, leptin receptor; POMC, pro-opiomelanocortin; PC1, prohormone convertase 1; MC4-R, melanocortin-4 receptor; ACTH, adrenocorticotropic hormone; α-MSH, α-melanocyte-stimulating hormone.