The diagnostic criteria for biochemical osteomalacia were serum levels of a 25-hydroxy vitamin D3 (25(OH)D) concentration < 30 nmol/L, a parathyroid hormone (PTH) concentration > 6.9 pmol/L and an alkaline phosphatase (ALP) concentration > 1.8 ukat/L. This evidence concerns the gene PTH and osteomalacia.