title: The polymorphism of Insulin-like growth factor-I (IGF-I) is related to osteoporosis and bone mineral density in postmenopausal population.
abstract: OBJECTIVE
  It has been shown that Insulin-like growth factor-1 (IGF-1) may be related with bone mineral density (BMD) or osteoporosis. But there are few evidences on the role of genetic variation of IGF-1 on the BMD or osteoporosis. We observed the relationship between polymorphisms of IGF-1(rs35767, rs2288377 and rs5742612) with osteoporosis and BMD in the postmenopausal female population in our study.
  
  
  METHODS
  A total of 216 postmenopausal women with a primary diagnosis of osteoporosis and 220 normal healthy women were included in the study. Genomic DNA of IGF-1 rs35767, rs2288377 and rs5742612 was extracted from the whole blood using QIAamp blood DNA mini kits (QIAGEN, Hilden, Germany) according to the methods recommended by the manufacturer.
  
  
  RESULTS
  We found that T allele of rs35767 had higher increased risk of osteoporosis (OR=1.34, 95%CI=1.0-1.81). Those carrying T allele of rs35767 had a significant lower BMD at L1-L4 vertebrae, femoral neck, total hip and trochanter when compared with those carrying C allele (P < 0.05). In addition, the BMD of L1-L4 vertebrae, femoral neck, total hip and trochanter decreased by 2.09%, 3.74%, 3.52% and 2.54% in women carrying T alleles compared with those carrying C alleles.
  
  
  CONCLUSIONS
  Our study suggests that polymorphism in IGF-I rs35767 was significantly associated with BMD and osteoporosis in postmenopausal female population, and polymorphism of rs35767 could be a marker for lower BMD and risk of osteoporosis.
authors.affiliation: Li Yun-Kai, The Fifth Surgical Department, The Fourth People's Hospital, Jinan, 250013, China.
authors.forename: Li
authors.initials: L
authors.lastname: Yun-Kai
authors.affiliation: Wang Hui, Department of Stomatology, Jinan Traditional Chinese Medicine Hospital,Jinan, 250012, China.
authors.forename: Wang
authors.initials: W
authors.lastname: Hui
authors.affiliation: Zhu Xin-wei, The Fifth Surgical Department, The Fourth People's Hospital, Jinan, 250013, China.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Xin-Wei
authors.affiliation: Guo Liang, Department of Radiotherapy, The Fourth People's Hospital, Jinan, 250013, China.
authors.forename: Guo
authors.initials: G
authors.lastname: Liang
authors.affiliation: Zuo Jin-liang, The Fifth Surgical Department, The Fourth People's Hospital, Jinan, 250013, China.
authors.forename: Zuo
authors.initials: Z
authors.lastname: Jin-Liang
keywords: Bone mineral density; Insulin-like growth factor-I; Osteoporosis; Polymorphism