RT Journal Article SR Electronic T1 Vitamin D deficiency associated with number of neurofibromas in neurofibromatosis 1 JF Journal of Medical Genetics JO J Med Genet FD BMJ Publishing Group Ltd SP 810 OP 813 DO 10.1136/jmg.2006.041095 VO 43 IS 10 A1 M Lammert A1 J M Friedman A1 H J Roth A1 R E Friedrich A1 L Kluwe A1 D Atkins A1 T Schooler A1 V-F Mautner YR 2006 UL http://jmg.bmj.com/content/43/10/810.abstract AB Neurofibromatosis 1 (NF1) is a tumour suppressor gene syndrome characterized by multiple cutaneous and plexiform neurofibromas. Focal osseous abnormalities, short stature, and decreased bone mineral density are also frequent in people with NF1. We measured serum 25-hydroxyvitamin D concentrations in 55 patients with NF1 and 58 healthy controls, and correlated the findings in the patients with NF1 with their estimated number of dermal neurofibromas. Geometric mean (SD) serum 25-hydroxyvitamin D concentration was 14.0 (1.6) ng/mL among the patients with NF1 compared with 31.4 (1.7) ng/mL among healthy controls (p<<0.0001). The serum vitamin D concentration and number of dermal neurofibromas reported by patients with NF1 were inversely correlated (Spearman’s ρ = −0.572, p<0.00001). The occurrence of low serum vitamin D concentrations in people with NF1, especially those with many dermal neurofibromas, may provide new pathogenic insights and have important therapeutic implications.