Krela-Kaźmierczak I, Michalak M, Wawrzyniak A, Szymczak A, Eder P, Łykowska-Szuber L, Kaczmarek-Ryś M, Drwęska-Matelska N, Skrzypczak-Zielińska M, Linke K, Słomski R
Department of Gastroenterology, Human Nutrition and Internal Diseases, University of Medical Sciences, Przybyszewskiego Street 49, 60-355, Poznan, Poland.
Department of Computer Science and Statistics, University of Medical Sciences, Poznan, Poland.
Mol Biol Rep. 2017 Dec;44(6):455-461. doi: 10.1007/s11033-017-4131-2. Epub 2017 Oct 9.
Gastrointestinal tract conditions are frequently associated with low bone mineral density and increased risk of fractures due to osteoporosis, the latter concerning particularly inflammatory bowel disease (IBD) patients. One of the candidate genes involved in osteoporosis is the transforming growth factor beta-1 (TGFB1) whose polymorphisms may be responsible for the development of this disease. The aim of this study was to analyse the frequency of TGFB1 polymorphic variants and determine the association between the c.29T>C TGFB1 polymorphism, and bone mineral density and fractures in IBD patients. The study subjects included 198 IBD patients [100 suffering from Crohn's disease (CD) and 98 from ulcerative colitis (UC)] and 41 healthy volunteers as a control group. Densitometric bone measurements were obtained using dual energy X-ray absorptiometry. The TGFB1 genotyping was conducted using restriction fragments length polymorphism. We conducted an analysis of genotype distribution's concordance with Hardy-Weinberg equilibrium. We found statistically significant differences in lumbar spine (L2-L4) and femoral neck BMD and T-scores between CD, UC and control subgroups. The distribution of TGFB1 polymorphic variants among CD and UC patients was concordant with Hardy-Weinberg equilibrium. There were no statistically significant differences in densitometric parameters (lumbar spine and femoral neck BMD, T-score, and Z-score) between carriers of different TGFB1 polymorphisms among IBD (CD and UC) patients nor among controls. We have found no statistically significant differences in the prevalence of low-energy fractures between groups of different TGFB1 polymorphic variant carriers. The allele dose effect, recessive effect and dominant effect analysis did not show an association between low-energy fractures and the TGFB1 polymorphisms among CD and UC patients. We have not observed an association between the c.29T>C TGFB1 polymorphic variant and the bone mineral density within the cancellous and cortical bones (L2-L4 and femoral neck, respectively), or the occurrence of fractures among the IBD patients and their family members.
胃肠道疾病常与骨矿物质密度低以及因骨质疏松症导致的骨折风险增加相关，后者尤其关乎炎症性肠病（IBD）患者。参与骨质疏松症的候选基因之一是转化生长因子β-1（TGFB1），其多态性可能是该疾病发生的原因。本研究的目的是分析TGFB1多态性变体的频率，并确定IBD患者中c.29T>C TGFB1多态性与骨矿物质密度及骨折之间的关联。研究对象包括198例IBD患者[100例患有克罗恩病（CD），98例患有溃疡性结肠炎（UC）]以及41名健康志愿者作为对照组。使用双能X线吸收法进行骨密度测量。采用限制性片段长度多态性进行TGFB1基因分型。我们对基因型分布与哈迪-温伯格平衡的一致性进行了分析。我们发现CD、UC和对照组亚组之间在腰椎（L2-L4）和股骨颈骨密度及T值上存在统计学显著差异。CD和UC患者中TGFB1多态性变体的分布符合哈迪-温伯格平衡。IBD（CD和UC）患者以及对照组中不同TGFB1多态性携带者之间的骨密度参数（腰椎和股骨颈骨密度、T值和Z值）没有统计学显著差异。我们发现不同TGFB1多态性变体携带者组之间低能量骨折的患病率没有统计学显著差异。等位基因剂量效应、隐性效应和显性效应分析未显示CD和UC患者中低能量骨折与TGFB1多态性之间存在关联。我们未观察到c.29T>C TGFB1多态性变体与松质骨和皮质骨（分别为L2-L4和股骨颈）内的骨矿物质密度之间存在关联，也未观察到IBD患者及其家庭成员中骨折的发生与该变体有关联。
