Relationship between Sp3 and the transcriptional regulation of enamelin gene / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the role of Sp3 in the transcriptional regulation of enamelin gene.</p><p><b>METHODS</b>By bioinformatic analysis, a putative responsive element for Sp3 was identified. Electrophoretic mobility shift assay was used to examine the interaction between Sp3 and enamelin. 5'-flanking regulatory region of enamelin was cloned and ligated into pGL3-basic luciferase vector. Sp3 and the Enam-luc were cotransfected into mouse ameloblast-like cell line, and the activity of luciferase was examined.</p><p><b>RESULTS</b>The results showed that Sp3 could not directly bind to the enamelin regulation region and activate enamelin transcription.</p><p><b>CONCLUSIONS</b>Sp3 might not be involved in transcriptional regulation of enamelin gene via an indirect interaction.</p>

Molecular Characterization of the NF2 Gene in Korean Patients with Neurofibromatosis Type 2: A Report of Four Novel Mutations / 대한진단검사의학회지

BACKGROUND: Neurofibromatosis type 2 (NF2) is an autosomal dominant syndrome caused by the NF2 tumor suppressor gene. However, the NF2 mutation characteristics in Korean patients are not sufficiently understood. In this study, we conducted a comprehensive mutational analysis in 7 Korean NF2 patients by performing direct sequencing and gene-dosage assessment. METHODS: We analyzed all exons and flanking regions of NF2 by direct sequencing and screened the deletions or duplications involving NF2 by multiplex ligation-dependent probe amplification. RESULTS: Four novel NF2 mutations, including 2 splice-site mutations (c.364-1G>A and c.886-3C>G), 1 frameshift mutation (c.524delA), and 1 missense mutation (c.397T>C; p.Cys133Arg), were identified in our patients. No large deletion or duplication was identified in our series. Subsequently, we identified an abnormal splicing product by using reverse transcription-PCR and direct sequencing in 2 patients with a novel splice-site mutation. The missense mutation c.397T>C was predicted to have harmful effects on protein function. CONCLUSIONS: The detection rate of NF2 mutations in Korean patients (57%) is similar to those in other populations. Our results provided a greater insight into the mutational spectrum of the NF2 gene in Korean subjects.

Polymorphisms of tumor necrosis factor-alpha promotor gene in Kawasaki disease and relation to the risk of coronary artery lesion / 소아과

PURPOSE: The purpose of this study was to investigate the polymorphisms of the TNF-alpha promotor gene, its susceptibility to Kawasaki disease (KD) and to assess whether the TNF-alpha promotor gene polymorphism was related the risk of coronary artery lesions (CALs). METHODS: From January 2003 to January 2007, 51 children (30 boys and 21 girls) with KD and 48 children forming an age-matched control group were studied. DNA from the peripheral blood of all the children was sampled, and the DNA polymorphisms of the 5' flanking regions of the TNF-alpha promoter gene at position -308 [guanine (G) to adenine (A)] were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Then, the relationship between KD and the TNF-alpha promotor gene polymorphisms was evaluated. RESULTS: The A allele frequency of the -308 site of the TNF-alpha promotor gene was 17.6% (9/51) for children with KD and 6.8% (3/48) for the control group children, but this result was not statistically significant. Twenty-four patients experienced CALs within 60 days after the onset of symptoms. KD children with TNF-alpha -308 A allele had lower frequencies of CALs (12.5% versus 22.2%, P>0.05). CONCLUSIONS: The DNA polymorphism of the -308 site TNF-alpha gene was not associated with susceptibility to KD and a risk of CALs. Multicenter, large-scale randomized controlled trials are needed for further study.

Analysis of polymorphisms in the 5'-flanking region of the apolipoprotein(a) [Apo(a)] gene in Thai subjects with coronary artery diseases.

Lipoprotein(a) [Lp(a)] is a complex lipoprotein particle in human plasma. It is composed of apolipoprotein B (Apo B)-100 and apolipoprotein(a) which are linked by a disulfide bond. Plasma levels of the Lp(a) vary greatly (over 1,000 folds) among individuals. Elevated plasma levels of the Lp(a) have been shown to be an independent risk factor for coronary artery diseases (CAD). The level of Lp(a) is controlled by a single gene, the Apo(a) gene, with multiple alleles; each encodes different concentrations of the Lp(a). Previous studies revealed the presence of polymorphisms in the 5'-flanking region (FL) of the Apo(a) gene at 3 positions: G or A (-914), C or T(-49), and G or A (-21), which can be detected by cleavage of PCR-amplified DNA products with TaqI, MaeII and HhaI, respectively. The 5'-FL genotypes of the Apo(a) gene can be classified by the combination of the presence (+) or absence (-) of these restriction sites into 5 types; type A, +++, type B, -++, type C, -+-, type D, --+ and type E, +-+. In the present study, the authors analyzed the 5' FL types of the Apo(a) gene by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) in 100 healthy control subjects, 26 CAD patients with [Lp(a)] < or = 30 mg/dL, and 94 CAD patients with [Lp(a)] > 30 mg/dL. The authors found that the genotype frequencies of the Apo(a) gene were 53, 16, 27 and 4%, for types A, B, C and D respectively in normal healthy controls. In CAD patients with [Lp(a)] < or = 30 mg/dL, the distribution of the genotype frequencies were 53.8, 11.5, 30.8 and 3.9% for types A, B, C and D, respectively. Additionally in CAD patients with [Lp(a)] > 30 mg/dL, the genotype frequencies were 60.6, 11.7, 21.3 and 6.4% for types A, B, C and D, respectively. The present study might shed some light to understand CAD at the molecular level.

The role of tonicity responsive enhancer sites in the transcriptional regulation of human hsp70-2 in response to hypertonic stress

The inducible 70 kDa heat shock proteins (Hsp70) in mice are encoded by two almost identical genes, hsp70.1 and hsp70.3. Studies have found that only hsp70.1 is induced by hypertonic stress while both hsp70.1 and hsp70.3 genes are expressed in response to heat shock stress. It is unclear if the human counterparts, hsp70-2 and hsp70-1, are differentially regulated by heat shock and osmotic stress. This study found that only hsp70-2 was induced by hypertonic stress in human embryonic kidney epithelial cells and fibroblasts, while heat shock stress induced both hsp70-1 and hsp70-2. The human hsp70-2 promoter region contains three TonE (tonicity-responsive enhancer) sites, which were reported to play an important role in the response to hypertonicity. When the reporter plasmids containing different parts of the 5' flanking region of hsp70-2 were transfected into human embryonic kidney epithelial cells or fibroblasts, one TonE site at -135 was found to play a key role in the response to hypertonicity. The inactivation of the TonE site using site-directed mutagenesis led to the complete loss of induction by hypertonicity, which demonstrates the essential role of the TonE site. This suggests that the TonE site and the TonEBP (TonE binding protein) are the major regulators for the cellular response against high osmolarity in human kidney tissue.

An analysis on transcriptional regulation activity of human XBP1 gene 5' upstream DNA sequences / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To analyze the transcription activation and possible regulation mechanism of human X-box binding protein 1(XBP1)gene 5'upstream DNA sequence in different cell lines.</p><p><b>METHODS</b>Six kinds of XBP1 promoter deletion mutants were cloned into pGEM-Teasy vector, which included XBP1 gene 5' upstream -1039 to 66 bp,-859 to 66 bp,-623 to 66 bp,-351 to 66 bp,-227 to 66 bp,-227 to -45 bp respectively. Every deletion mutant sequence was cut from Teasy-XBP1p by KpnI and Xho I, and subcloned into pCAT3-Basic to produce a set of constructs termed as p1-XBP1p, p2-XBP1p, p3-XBP1p, p4-XBP1p, p5-XBP1p, p6-XBP1p, respectively. The transcription activity of each construct was detected after transiently transfecting K562, HepG2,NIH-3T3 and L0(2)cell with FuGENE 6 transfection reagent. Cells transfected by pCAT3-Basic or pCAT3-Promoter were used as negative and positive controls. The activity of chloramphenicol acetyltransferase(CAT), which reflects the transcription activation of the XBP1 gene promoter, was detected by ELISA after 48 hours of transfection.</p><p><b>RESULTS</b>The reporter vectors of six kinds of XBP1 promoter deletion mutants were successfully constructed, as confirmed by restriction enzyme digestion and sequencing. The activities of p4-XBP1p and p5-XBP1p were higher than the other deletion mutants in K562 and HepG2. And the activity of p5-XBP1p was the highest in HepG2. There was no activity detected from any transfected NIH-3T3.</p><p><b>CONCLUSION</b>The XBP1 gene promoter can transactivate its downstream gene to transcription. The core sequence of XBP1 promoter was implied between -227 bp and 66 bp. This sequence was connected with the transcriptional activity of XBP1 promoter closely. Its transcription activity varies with different cell lines. XBP1 promoter might drive gene expression with cell-type specificity.</p>

Effect of variation in 5'-regulatory region of insulin receptor substrate-1 gene on gene expression / 中南大学学报(医学版)

UNLABELLED@#OBJECTIVE; To determine the effect of a variation of CAG-rich region, which was found in the 5'-regulatory sequence of insulin receptor substrate-1(IRS-1) gene in Type 2 diabetes mellitus(T2DM) patients, on gene expression and its mechanism.@*METHODS@#The recombinants, pGL2.P-T3 and pGL2.P-T5, were constructed with luciferase reporter vector, pGL2 promoter. T3 and T5 were wild-type and variant alleles, respectively. The recombinants were cotransfected with pSV-beta-galactosidase control vector to Hela cells. Luciferase assay was performed to assess transcriptional activity. The electrophoresis mobility shift assay(EMSA) and DNA footprint assay were applied to determine the interaction between the DNA regulatory sequences and nuclear proteins of Hela cells.@*RESULTS@#The relative transcription activity of T5 was lower than that of T3 [(7.76+/-1.05)% vs (9.98+/-1.40)%, P<0.05]; EMSA showed both T3 and T5 formed a single retarded band in gel with the same mobility with nuclear proteins; T5 had 2 binding sites for transacting factors, CGCGCCCGCGGGCGGCGGC and GGGCGGCTGGTGGCGGCTG, which was the same as T3.@*CONCLUSION@#Although the variation in T5 do not alter the DNA-binding sites for Hela cell nuclear extracts, the notable decrease in gene transcription activity induced by it may be an important factor to the development T2DM in the carrier.

Gene Regulatory Regions Required for beta Defensin-2 Up-Regulation by Interleukin-1alpha in the Human Middle Ear Epithelial Cell Line / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Innate immunity is important in the middle ear because of the lack of immune cells in the region. Among innate immunities beta-defensin-2 is known to play an important role in the immune function of the middle ear. But we still do not understand well about the signal transduction pathway and gene regulatory region of beta-defensin-2 (hBD-2). MATERIALS AND METHOD: The expression of beta-defensin-2 (hBD-2) by IL-1alpha in HMEEC was detected by RT-PCR. The luciferase-expressing vector containing diverse lengths of the hBD-2 5' flanking region made by the progressive unidirectional deletion was transferred to HEEMC (Human Middle Ear Cell). We analyzed the function of 5' flanking region by luciferase activity measured using a luminometer after supplementing corresponding substrates to the cell lysate. RESULTS: hBD-2 was upregulated by IL-1alpha in HMEEC-1. The treatment of IL-1alpha up-regulated the activity of promoter by 7.60+/-1.45 (average+/-standard deviation) folds in 2.7 kpb sized 5' flanking region, 3.81+/-0.78 folds in 1.1 kbp, and 4.00+/-0.73 folds in 500 bp. CONCLUSION: These results indicate there are two effective gene regions that regulate the hBD-2 expression by IL-1alpha between 2.7 kbp and 1.1 kbp, and at 500 bp upstream of the translation starting point of hBD-2 in HMEEC-1.

The relationship between the variants in 5' upstream core promoter A(-6)G and A(-20)C of angiotensinogen gene and essential hypertension in Kazakans of Xinjiang / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate whether the variants A(-6)G and A(-20)C of angiotensinogen (AGT) gene are involved in the pathogenesis of essential hypertension in Kazakans.</p><p><b>METHODS</b>T his case control study recruited 125 subjects with hypertension and 74 normotensive subjects from Kazakans of Xinjiang. Genomic DNA from leukocytes was analyzed for genetic variants A(-6)G and A(-20)C in 5' upstream core promoter of AGT gene by polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP), restriction fragment length polymorphism (RFLP) and automatic sequencing.</p><p><b>RESULTS</b>(1)There were only A(-6)G and A(-20)C variants in the -164 to +73 region of Kazakans' AGT gene. (2) The distributions of genotypes AA, AG, GG at locus -6 of AGT gene showed significant difference between the hypertensive group (0.39, 0.45, 0.16) and the normotensive group (0.49, 0.49, 0.02; Chi2=8.56, P=0.014). There were evident differences in the frequencies of the -6A and the -6G allele of the two groups (0.62, 0.38 and 0.73, 0.27; Chi2=5.35, P=0.021). (3) No significant difference was observed in the distribution of genotypes AA, AC, CC at locus -20 of AGT gene between the hypertensive group (0.69, 0.26, 0.05) and the normotensive group (0.65, 0.32, 0.03; Chi2=2.42, P=0.30). There was no distinct difference in the frequencies of the -20A allele and the -20C allele of the two groups (0.82, 0.18 and 0.82, 0.18; Chi2=0, P=0.99). (4) No significant difference was found at the levels of systolic and diastolic blood pressure between the groups corresponding to genotypes at the loci -6 and -20 of AGT gene.</p><p><b>CONCLUSION</b>The results suggest that the polymorphism of A(-6)G in 5' upstream core promoter of the AGT gene may be involved in the pathogenesis of essential hypertension in Kazakans, while the A(-20)C variant may not play an important role in the etiology of essential hypertension in Kazakans.</p>

Primary functional analysis of CK13 gene 5' flanking region / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the mechanism of cytokeratin 13 (CK13) gene expression control and the effects of different motifs of CK13 gene 5' flanking region on its transcriptional activity.</p><p><b>METHODS</b>The molecular clone technique and reporter gene analysis were used to assay the effects of different motifs of 513 bp of CK13 gene 5' flanking region on its transcriptional activity. The pCAT enhancer vectors with different motifs of CK13 gene 5' flanking region were constructed and transferred to HeLa cells with the help of lipofectin. The instant CAT expression of different clones was detected and the effects of different motifs of the CK13 gene 5' flanking region on its transcriptional activity were evaluated.</p><p><b>RESULTS</b>119 bp from -nt.325 to -nt.207 upstream of the first ATG of CK13 gene 5' flanking region included a silent element. 113 bp region from -nt.206 to -nt.94 included an enhanced element.</p><p><b>CONCLUSION</b>513 bp of CK13 gene 5' flanking region includes a silent element and an enhanced element. Further locating these cis elements and detecting the related trans reaction factors may unveil some important clues to the details of the mechanisms for the CK13 gene expression and tissue-specific expression.</p>

Structural characterization of 5' flanking regulatory region of DNA repair gene Rad51 / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To clarify the regulatory elements of Rad51 gene in its 5'flanking region.</p><p><b>METHODS</b>Various constructs were obtained by cloning different DNA fragments into pGL3 reporter vector. These constructs were then introduced into osteosarcoma cell line U2-OS by calcium phosphate method for transient expression of reporter gene, and luciferase activities were measured by luciferase assay.</p><p><b>RESULTS</b>Cells transfected with pGL3 constructs containing fragment -964 to +1430 and -733 to +1430 showed high luciferase activities. Obvious elevation of luciferase activities was also observed in cells transfected with pGL3 constructs containing four shorter derivative fragments -964 to -412, -746 to -412, -651 to -412 and -536 to -412. The highest luciferase activities were measured in transfected cells with plasmids containing fragment -964 to -412, and the lowest were in transfected cells with plasmids containing fragment -536 to -412. Luciferase activities in transfected cells with plasmids containing fragment -651 to -412 were higher than that in transfected cells with plasmids containing fragment -746 to -412.</p><p><b>CONCLUSION</b>It is believable that the basic transcription-promoting element (promoter) for Rad51 gene resides between -536 to -412, and two transcription-enhancing elements (enhancer) or binding sites of positive transcription factors reside between -651 to -536 and -964 to -746, whereas one transcription-inhibiting element (silencer) or binding site of negative transcription factor may reside between -746 to -651.</p>

Conservation of Mucous Epithelial Characteristics in the Human Middle Ear Epithelial Cell Line / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The stable cell line system of middle ear epithelial cells is essential for studying molecular pathogenesis of otitis media. Recently, we succeeded in establishing the human middle ear epithelial cell line (HMEEC) using a retrovirus. The cell line retains many of the phenotypic and morphological properties of the non-transformed, parental cultures such as the expression of cytokeratin and tight junctions. We aimed to show the conservation of mucosal characteristics and subcellular mechanisms of transcriptional regulation in this cell line. MATERIALS AND METHOD: RT-PCR was performed using mucin gene specific primers and total RNA extracted from HMEEC. The luciferase-expressing vector containing 5' flanking region of human beta defensin 2 (hBD-2), an inducible antimicrobial peptide, was transfected to HMEEC. After starvation of serum, HMEEC was treated with interleukin 1 alpha (IL-1alpha) and subsequently harvested 10 hrs later. Luciferase activity was measured using luminometer after the corresponding substrate was supplemented to the cell lysate. RESULTS: Expression of mucin genes (MUC1, 2 and 5B) in HMEEC was demonstrated by RT-PCR. Luciferase assay showed that IL-1alpha up-regulates the promoter activity of hBD-2 more than 10 fold. This transcriptional regulatory mechanism was also demonstrated in the well established reference cell lines, HeLa cells and A549 cells. CONCLUSION: We demonstrated the conservation of mucin gene expression and transcriptional regulatory mechanism of hBD-2 in HMEEC. The proposed cell line can serve as a useful experimental model for elucidating the pathogenesis of middle ear mucosa-related diseases.

The regulating effect of antisense-S-Oligo on TYR gene expression and melanin production of melanocytes / 中华整形外科杂志

<p><b>OBJECTIVE</b>Despite the causes for melanin increase, the increased gene expression of TYR is a common pathological process. Based on this viewpoint, antisense-S-Oligo of TYR was designed and synthesized to regulate synthesis of melanin in order to explore the treatment for skin pigmentation.</p><p><b>METHODS</b>The cultured melanocytes were divided into 3 groups. The group 1 was treated with endothelin, group 2 treated with ultraviolet ray and group 3 was used as the control. In each group, the 5' antisense-S-Oligo, the 3' antisense-S-Oligo, the mixed antisense-S-Oligo of TYR or Dotap only was added. The melanin content and TYR gene expressions were examined.</p><p><b>RESULTS</b>The 5' antisense-S-Oligo, the 3' antisense-S-Oligo and the mixed antisense-S-Oligo significantly inhibited the increase of melanin content and TYR gene expression, which were caused by endothelin or ultraviolet ray treatment. Of the three treatments, the 3' antisense-S-Oligo showed the strongest effect.</p><p><b>CONCLUSION</b>Antisense-S-Oligo has significant regulating effects on TYR gene expression and melanin content. The 3' antisense-S-Oligo is more effective than the 5' antisense-S-Oligo.</p>

Sequence analysis of 5'-flanking region of human pax-5 gene exon 1B / 中国实验血液学杂志

Pax-5 gene is important transcription factor in B-lymphopoiesis and B-cell development. To understand the regulatory mechanism of pax-5 expression, the immediate 5'-flanking region (6 671 bp) of human pax-gene exon 1B was isolated and characterized. Analysis of the total sequence showed that the proximal promoter includes 3 CAT boxes, 1 SP1 and 1 E box. However, there was no consensus sequence for a TATA box in the 5'-flanking region. Putative regulatory sites of further upstream in the sequence revealed 6 LMO(2)COM, 5 NFAT, 2 LPOLYA-B, 3 GATA1, 2 AP4, 10 MZF1, 1 ETS1-B, 1 GATA3, 1 NKX25, 2 RORA1, 1 LYF1, 2 Ikaros2, 2 TCF11, 1 GATA-C and 1 FREAC7. Therefore, the 5'-flanking region of human pax-5 exon 1B could be involved in regulating the expression of human pax-5 and B-cell differentiation and development.

Identification of AP1 cis-element and transcriptional effect on cytokeratin 13 gene expression / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To identify the type of CTGAATCA from -nt.199 to -nt.192 of the cytokeratin 13(CK13) gene 5' flanking region and determine its transcriptional effect on CK13 gene expression.</p><p><b>METHODS</b>The CAT systems were used to assess the effects of different motifs of CK13 gene 5' flanking region on transcription. The clones of pCAT-enhancer with the total length, -nt.207 to +nt.63 and the same length of -nt.207 to +nt.63, but the T, G of -nt.198, -nt.197 being changed to A, T of the CK13 gene 5' flanking region, were constructed and transferred to HeLa cells with the help of lipofectin. Then work was done to detect the instant CAT expression of different clones and evaluate the effects of CTGAATCA of the 5' flanking region on CK13 gene expression. The type of the cis-element of CTGAATCA was identified with electrophoretic mobility shift assay (EMSA) and competition-EMSA.</p><p><b>RESULTS</b>CTGAATCA in the CK13 gene 5' flanking region is an AP1 cis-element by EMSA and competition-EMSA, it promotes CK13 gene expression.</p><p><b>CONCLUSION</b>CTGAATCA from -nt.199 to nt.192 of the CK13 gene 5' flanking region is an AP1 reaction element, not a cAMP reaction element. It promotes transcriptional activity of CK13 gene 5' flanking region.</p>

Cloning of 5', 3' flanking sequence of ovine BLG and regulating the expression of GFP in mammary gland cell line / 生物工程学报

5' and 3' flanking region of ovine BLG were amplified from sheep genomic DNA according to the published whole sequence of ovine BLG and cloned to pGEM-T vector correspondently. By partially sequencing, the sequences of BLG 5' and 3' flanking were the same as that of publication completely. The recombinant structure used to direct exogenous gene especially to express in mammary gland was constructed by joining 4.2 kb 5' flanking with 2.1 kb 3' flanking. In order to assess the efficiency of BLG regulatory elements, green fluorescent protein (GFP) gene as a reporter was fused with BLG construct and transfected the mammary epithelial cells (TD47). Through observation under UV microscope and detection by fluorometer, it is demonstrated that the GFP has been successfully expressed in TD47 cell line. By virtue of direct observation and quantitative analysis, the BLG-GFP construct can be served as a model for the quick assessment of mammary gland expression construct.

Polymorphisms and functions of the aldose reductase gene 5' regulatory region in Chinese patients with type 2 diabetes mellitus / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To screen the 5' regulatory region of the aldose reductase (AR) gene for genetic variabilities causing changes in protein expression and affecting the promoter function.</p><p><b>METHODS</b>The screenings were carried out by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). All SSCP variants were submitted for DNA sequencing and inserted into the plasmid chloromycetin acetyl transferase (CAT) enhancer vector. The constructs were used to transfect Hela cells, and CAT assays were performed to assess promoter activity. Gel mobility shift and footprinting assays were also performed to determine the interaction between the DNA and nuclear proteins.</p><p><b>RESULTS</b>Two polymorphisms, C (-106) T and C (-12) G, were identified in the regulatory region in 123 Chinese control subjects and 145 patients with type 2 diabetes mellitus. The frequencies of genotypes WT/WT, WT/C (-12) G and WT/C (-106) T were not significantly different between the subjects and patients. In the patients with and without retinopathy, frequencies of WT/C (-106) T were 31.5% and 17.5% (P < 0.05) respectively, and the frequencies of WT/C (-12) G were 10.5% and 2.5% (P > 0.05) respectively. The total frequency of WT/C (-12) G and WT/C (-106) T in patients with retinopathy was 41.8%, significantly higher than that (20.0%) in patients without retinopathy (P < 0.025). The relative transcription activities of the wild-type, the C (-12) G and the C (-106) T were 15.7%, 31.0% and 32.2%, respectively. The results of DNA-protein interaction assays showed that these variations did not change the binding site of DNA with trans-acting factors.</p><p><b>CONCLUSION</b>The polymorphisms C (-12) G and C (-106) T strongly associated with diabetic retinopathy in the Chinese population have been identified in the regulatory region of the aldose reductase gene.</p>