Two studies reported on the association between vitamin D receptor and osteoprotegerin (OPG) polymorphisms, with tumour necrosis receptor associated factor 6 genotype associations in one study.33 34 Patient-related factors, including body composition, sarcopenia, foot and ankle characteristics and pain in relation to osteoporosis, fractures and falls were studied in three studies.35, 37 Dizziness, visual impairment and vertigo as falls associated factors were studied in two papers.38 39. Here, VDR is linked to osteoporosis.