Table 4.

Analysis between syndromic symptoms and risk genes

Syndromic symptoms	Families	Cases	Gene association
FMTC/MEN2A	16	29	RET
Waardenburg syndrome	12	22	EDNRB/EDN3, RET/PAX3, ERBB3
Bardet–Biedl syndrome	3	6	–
Special physical characteristics	1	3	EDNRB
Respiratory symptoms	1	3	PHOX2B
External auditory canal agenesis	1	2	ERBB3
Anisocoria	1	2	PHOX2B
Multiple sclerosis	1	2	EDNRB
Congenital central hypoventilation syndrome	1	2	PHOX2B
Currarino syndrome	1	2	–
Neuroblastoma	1	2	–
Congenital heart disease	1	1	PHOX2B
Trisomy 21	1	1	–
Meningocele	1	1	–
Intellectual disability	1	1	RET/BBS

Special physical characteristics include telecanthus, prominent nasal bridge, broad nasal bridge, tapering fingers, widely spaced nipples, low set ears, short neck, thoracic scoliosis, mild syndactyly and broad hallux. FMTC familial medullary thyroid cancer, MEN2A multiple endocrine neoplasia type 2a, RET ret proto-oncogene, EDNRB endothelin B receptor gene, EDN3 endothelin 3 gene, PAX3 paired box 3 gene, ERBB3 v-erb-b2 erythroblastic leukemia viral oncogene homolog 3 gene, PHOX2B paired like homeobox 2B gene, BBS Bardet–Biedl gene. “–” no data