Table 2.

Heritability estimates for radiographic phenotypes, after adjustment for age, gender and body mass index

	All subjects		Caucasians only
Phenotype	Heritability estimate (SE)	P value	Heritability estimate (SE)	P value
First IP count	0.63 (0.15)	0.00004	0.70 (0.15)	0.00001
DIP count	0.36 (0.1643)	0.02	0.36 (0.17)	0.019
PIP counta	0.30 (0.16)	0.03	0.28 (0.17)	0.04
DIP/IP/PIP counta	0.42 (0.16)	0.004	0.41 (0.16)	0.006
CMC count	0.38 (0.17)	0.01	0.46 (0.17)	0.005
Total counta	0.38 (0.16)	0.008	0.38 (0.16)	0.01
First IP scorea	0.84 (0.14)	0.0000001	0.89 (0.14)	2.70 × 10-9
DIP scorea	0.18 (0.16)	0.12	0.16 (0.17)	0.17
PIP scorea	0.16 (0.15)	0.15	0.14 (0.16)	0.18
DIP/IP/PIP scorea	0.33 (0.16)	0.02	0.33 (0.16)	0.02
CMC score	0.53 (0.16)	0.0006	0.63 (0.16)	0.0001
Total scorea	0.35 (0.16)	0.01	0.36 (0.16)	0.01
Subchondral cystsa	0.17 (0.15)	0.13	0.13 (0.16)	0.20
Joint subluxationa	0.27 (0.17)	0.06	0.19 (0.19)	0.15
Joint space narrowinga	0.24 (0.16)	0.06	0.18 (0.17)	0.14
Subchondral sclerosisa	0.17 (0.16)	0.14	0.15 (0.17)	0.18
Erosionsa	0.12 (0.14)	0.20	0.13 (0.15)	0.20
Joint deformitya	0.31 (0.20)	0.06	0.15 (0.20)	0.24
Heberden's nodes	0.36 (0.22)	0.07	0.21 (0.23)	0.19

CMC, carpometacarpal joint; DIP, distal interphalangeal joint; IP, interphalangeal joint; PIP, proximal interphalangeal joint; SE, standard error. ^aTransformed by square root. Statistically significant results are represented in bold.