Table 2.

Selected genes with variants contributing to severe monogenic obesity with recent reviews

Gene symbol	Full name	Location	Obesity	Associated traits	Recent reviews
ADCY3	Adenylate cyclase 3	2p23.3	Severe-early onset	Type 2 diabetes	Tian et al. 2018 [10]
BDNF	Brain-derived neurotrophic factor	11p14.1	Severe-early onset	Hyperphagia, severe obesity, hyperactivity and impaired cognitive function.	Han et al. 2016 [11]
KSR2	Kinase suppressor of ras 2	12q24.22-q24.23	Severe	Hyperphagia (in childhood), insulin resistance and reduced basal metabolic rate.	Frodyma et al. 2017 [12]
LEP	Leptin	7q32.1	Severe, early onset	Hyperphagia, hypogonadotropic hypogonadism. Some evidence for neuroendocrine/metabolic and immune dysfunction	Wasim et al 2016; Yeo 2017 [13, 14]
LEPR	Leptin receptor	1p31.3	Severe, early onset	Hyperphagia, hypogonadotropic hypogonadism. Some evidence for neuroendocrine/metabolic and immune dysfunction	Wasim et al 2016; Yeo 2017 [13, 14]
MC4R	Melanocortin 4 receptor	18q21.32	Severe, early onset	Increased linear growth and final height, fasting hyperinsulinemia and incompletely suppressed growth hormone secretion.	Krashes et al 2016; Yeo 2017; Novoselova et al 2018 [14–16]
PCSK1	Proprotein convertase subtilisin/kexin type 1	5q15	Severe – occurring in childhood	Hyperphagia, impaired glucose homeostasis, decreased linear growth, hypothyroidism, hypocortisolism and hypogonadotropic hypogonadism	Ramos-Molina et al 2016; Stijnen et al 2016 [17, 18]
POMC	Proopiomelanocortin	2p23.3	Severe, from the first months	Adrenocorticotropic hormone (ACTH) deficiency, red hair and pale skin	Anderson et al 2016; Rubinstein and Low 2017 [19, 20]