Table 2.
Major syndromic causes of pediatric obesity, classified according to estimated prevalence
| Syndrome | OMIM | Gene(s) involved | Estimated prevalence | Major clinical features |
|---|---|---|---|---|
| Prader-Willi syndrome (PWS) [111] | #176270 | 15q11-q13 deletion/maternal uniparental disomy | 1 in 10,000–30,000 | Neonatal hypotonia, hyperphagia, severe obesity, hypogonadism, short stature, intellectual disability |
| Bardet-Biedl syndrome (BBS) [63] | #209900 (genetically heterogeneous, this is the primary phenotype entry) | BBS1, BBS2, ARL6 (BBS3), BBS4, BBS5, MKKS (BBS6), BBS7, TTC8 (BBS8), PTHB1 (BBS9), BBS10, TRIM32 (BBS11), BBS12, MKS1 (BBS13), CEP290 (BBS14), WDPCP (BBS15), SDCCAG8 (BBS16), LZTFL1 (BBS17), BBIP1 (BBS18), IFT27 (BBS19), IFT172 (BBS20), C8orf37 (BBS21), IFT74 (BBS22) | 1 in 100,000–160,000 in general populations (higher in consanguineous populations) | Cone–rod dystrophy, polydactyly, obesity, renal anomalies, cognitive impairment |
| Alström syndrome [112] | #203800 | ALMS1 | < 1 in 1,000,000 | Progressive vision and hearing loss, obesity, insulin resistance, cardiomyopathy |
| Smith-Magenis syndrome [35] | #182290 | 17p11.2 deletion (RAI1) | 1:25,000–50,000 | Sleep disturbances, intellectual disability, behavioral problems, obesity |
| WAGR syndrome [35] | #194072 | 11p13 deletion (including WT1 and PAX6) | 1 in 500,000–1,000,000 | Wilms tumor, aniridia, genitourinary anomalies, intellectual disability, obesity |
| Cohen syndrome [35] | #216550 | VPS13B | < 1 in 100,000 | Obesity, intellectual disability, microcephaly, retinal dystrophy, hypotonia |
| Simpson-Golabi-Behmel syndrome [35] | #312870 (X-linked form, most common) | GPC3 | < 1 in 100,000, exact prevalence unknown | Pre- and postnatal overgrowth, obesity, coarse facial features, increased tumor risk |
| Carpenter syndrome [35] | #201000 | RAB23 | < 1 in 1,000,000 | Craniosynostosis, polydactyly, obesity, developmental delay |
| Albright Hereditary Osteodystrophy [113] | #103580 (: overlaps with pseudohypoparathyroidism spectrum) | GNAS | rare; prevalence unclear | Short stature, obesity, round face, subcutaneous calcifications, resistance to PTH ± other hormones |
Abbreviations: OMIM, Online Mendelian Inheritance in Man.