Lee Yong-Wha
Department of Laboratory Medicine and Genetics, Soonchunhyang University Bucheon Hospital and Soonchunhyang University College of Medicine, Bucheon, Gyeonggi 420-767, Republic of Korea.
Exp Ther Med. 2013 Dec;6(6):1532-1534. doi: 10.3892/etm.2013.1326. Epub 2013 Oct 4.
Primary renal glucosuria (PRG; OMIM #233100) is characterized by persistent glucosuria due to a reduction in the renal tubular reabsorption of glucose in the presence of a normal concentration of serum glucose and the absence of any other impairment of tubular function. The gene is the causative gene, which codes for the low-affinity sodium/glucose co-transporter SGLT2. In the present study, the case of a patient with PRG associated with a novel mutation of the gene is reported. The patient visited hospital for the evaluation of glucosuria in the absence of hyperglycemia, a condition that had been present for >20 years. The patient showed a fasting blood sugar level of 104 mg/dl, a 2-h postprandial sugar level of 101 mg/dl, a sodium level of 144 mmol/l, a potassium level of 3.7 mmol/l and a chloride level of 106 mmol/l in serum. Urine chemistry revealed that the amount of glucose excreted was 10.8 g/1.73 m/24 h; however, the levels of the other parameters were unremarkable. Polymerase chain reaction (PCR) sequencing analysis of the gene from the patient revealed a novel 1 bp deletion mutation, which altered the coding sequence of exon 10 in the transmembrane domain (c.1162delG; Ala388ProfsX48), suggesting an autosomal dominant inheritance pattern. This study identified a novel mutation in the gene related to a benign clinical characteristic and suggests that the molecular diagnosis of the gene may be useful for diagnosing renal glucosuria in patients and for deciding intervention measures for their family members.
原发性肾性糖尿（PRG；OMIM #233100）的特征是在血清葡萄糖浓度正常且不存在任何其他肾小管功能损害的情况下，由于肾小管对葡萄糖的重吸收减少而导致持续性糖尿。该基因是致病基因，编码低亲和力钠/葡萄糖协同转运蛋白SGLT2。在本研究中，报告了一例与该基因新突变相关的PRG患者病例。该患者因无高血糖情况下的糖尿评估而就诊，这种情况已存在20多年。患者血清空腹血糖水平为104 mg/dl，餐后两小时血糖水平为101 mg/dl，钠水平为144 mmol/l，钾水平为3.7 mmol/l，氯水平为106 mmol/l。尿液化学分析显示，葡萄糖排泄量为10.8 g/1.73 m²/24 h；然而，其他参数水平无异常。对该患者的该基因进行聚合酶链反应（PCR）测序分析，发现一个新的1 bp缺失突变，该突变改变了跨膜结构域中外显子10的编码序列（c.1162delG；Ala388ProfsX48），提示为常染色体显性遗传模式。本研究鉴定了该基因中与良性临床特征相关的一个新突变，并表明该基因的分子诊断可能有助于诊断患者的肾性糖尿以及为其家庭成员确定干预措施。
