Further evidence supporting a genetic background for Paget's disease of bone in Spain

The aim of this paper is to investigate heritable factors that might be related to the recognised genetic susceptibility for developing Paget's disease of bone (PD). This was a hospital-based, case-control study of a systematically selected group of PD patients and a group of controls drawn from the same health setting. In these populations we assessed surname pattern, parental consanguinity and constitutional physical traits. In a separate case-control analysis, genetically-based features and pathological traits of interest for genetic inference in 43 demonstrated familial cases were then compared to those in 24 sporadic cases. Results showed coincidence of three or four surnames (Odds Ratio [OR] = 5.6; 95% CI = 1.7-18.5), degree of parental consanguinity (OR = 4.1; 95% CI = 2.1-1.8), and green or blue eye colour (OR = 1.5; 95% CI = 1.1-2.1) were significantly associated with PD. Comparison of proven familial and sporadic PD cases showed that the former had a stronger association with Monckeberg-type vascular calcifications (32% vs. 4%; p = 0.02), percentage of skeleton affected (13.1 vs. 9.0), and green and blue eye colour (82% vs. 25%; p = 0.006), with Monckeberg-type vascular calcifications being the main variable of interest (OR = 30.9; 95% CI = 12.75-347.00) in the multivariate analysis. In conclusion, heritable factors are crucial in the pathogenesis of PD and, in line with other data sources, might account for the ethnic predisposition observed in different countries.