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Biomedical subjects

Ming Ding

Publications and source records attributed to Ming Ding.

At least 19 recordsLinked to original sources

Loss of RAB25 expression in breast cancer.

A novel breast cancer cell line (RAO-3) was established by transduction of the Q61L mutant RAS into human mammary epithelial cells that were immortalized with catalytic subunit of telomerase (hTERT). The cells displayed anchorage-independent growth and proliferation, and formed human mammary spindle cell carcinoma when injected into nude mice. Chromosome locus 1q22-23 was partially duplicated and inverted on one of the 3 chromosomes present in the cell line. We report here that mutations of chromosome 1q22-23 locus have resulted in the loss of RAB25 expression in the breast cancer cell line. Transduction of RAB25 into the breast cancer cell line arrests anchorage-independent growth. We have also demonstrated loss of RAB25 in human breast tumor tissue. These data suggest that loss of RAB25 might contribute to tumorigenesis of breast cancer, and RAB25 is likely to be an important factor in the development of breast cancer. RAB25 could be used as biological marker of breast cancer and provides a target for gene replacement therapy.

Animals↗

mRNA expression in mouse hypothalamus and basal forebrain during influenza infection: a novel model for sleep regulation.

After influenza infection, C57BL/6J mice develop increased slow-wave sleep (SWS) during the dark phase of the day-night cycle, whereas BALB/cByJ mice develop decreased SWS during the light phase. A previous analysis of CXB recombinant inbred mice revealed a quantitative trait locus (QTL) designated Srilp (sleep response to influenza, light phase) that was related to expression of the BALB/cByJ sleep phenotype. Srilp was localized to the 10- to 12-cM region of mouse Chr 6 between D6Mit74 and D6Mit188. Temt (thioether S-methyltransferase), which is located at region B3 of Chr 6, is a potential candidate gene for Srilp. We evaluated the expression of Temt and other Srilp candidate genes in hypothalamus and basal forebrain of uninfected and influenza-infected C57BL/6J and BALB/cByJ mice. We report here that Temt expression varies significantly with respect to mouse strain, health status, brain region, and day-night phase. C57BL/6J mice show day-night variation in Temt expression in hypothalamus, but BALB/cByJ mice do not. Temt expression in basal forebrain is much higher in C57BL/6J mice than in BALB/cByJ mice. During influenza infection, both C57BL/6J and BALB/cByJ mice show reduced Temt mRNA in basal forebrain at 30 h postinoculation, but expression remains much lower in the BALB/cByJ strain. In contrast, prostaglandin-D-synthase (Ptgds) and lipocalin 2 (Lcn2) mRNA increase in basal forebrain of both strains after influenza infection. Administration of the TEMT inhibitor sinefungin reduces sleep in uninfected BALB/cByJ mice and attenuates influenza-induced sleep enhancement in C57BL/6J mice. These data suggest that strain- and infection-related alterations in sleep may be influenced by Temt expression and perhaps by subsequent effects on prostaglandin metabolism.

Acute-Phase Proteins↗

Investigation on bioremediation of oil-polluted wetland at Liaodong Bay in northeast China.

An investigation on the effect of various microbes on degradation was carried out as part of the study on bioremediation of oil-polluted wetland at LiaoDong Bay in northeast China. The method used involved direct inoculation of selected bacteria, which were capable of degrading oil, to the soil samples. The combination of various bacteria showed better results in terms of oil degradation than any single ones due to their synergetic effects. The operation conditions [pH 8.0, 25 degrees C, C/N/P (40:5.6:1)] for these bacteria to degrade the oil content in the soil samples were also studied and optimized. Addition of appropriate surfactants was helpful for bacteria growth, thus favoring the oil degradation. For instance, after adding Tween 80 (300 mg/kg) for 8 days, the number of bacteria was amplified 6.22 times and the rate of oil degradation increased by 20%. Adequate amount of H2O2 was also beneficial for microbes to decompose oil. However, overdosage may cause the death of the bacteria. The addition of 400 mg/l H2O2 each time was suitable. Seven thousand milligrams of H2O2 was added entirely in 11 days, and the rate of oil degradation increased significantly from 27% (without H2O2) up to 67%. The study clearly demonstrated that the direct soil inoculation was an effective method for environmental bioremediation.

Biodegradation, Environmental↗

A synthetic gonadotropin-releasing hormone (GnRH) vaccine for control of fertility and hormone dependent diseases without any adjuvant.

Active immunization against self-peptides have gained widespread acceptance inspite of their low immunogenicity. Recent applications involving multiple copies of self-peptides in linear alignment and conjugation with carrier proteins appear to increase the immune response against self-peptides. As with most vaccines, however, immunogens require supplementation with adjuvants to elicit an optimum immune response. In the present study, we prepared a double-chain mini-protein with each chain containing three linear repeats of the self-peptide gonadotropin-releasing hormone (GnRH3), the hinge region of human IgG1 (hinge), and a T-helper epitope from the measles virus protein (MVP). The GnRH3-hinge-MVP mini-protein was conjugated to purified recombinant heat shock protein 65 (Hsp 65) of Mycobacterium bovis and used to immunize rats primed with subcutaneous injections of Bacillus Calmette-Guerin (BCG) in the absence of adjuvants. The GnRH3-hinge-MVP-Hsp 65 stimulated the production of specific anti-GnRH antibodies in the absence of adjuvants and the antibody titer was comparable to that produced in rats immunized with the dimeric mini-protein in the presence of Freund's adjuvant. Moreover, immunization with the adjuvant-free GnRH3-hinge-MVP-Hsp 65 induced degeneration of the reproductive organs in both male and female rats unlike those immunized in the absence of Hsp 65 or in control animals inoculated with the vehicle only. Histological examination of the affected organs showed atrophy of the seminiferous tubules with diminished spermatogenesis in the testes of male rats. In female rats, the uteri were much smaller in size and the ovaries exhibited reduced follicular development. These findings demonstrated that GnRH3-hinge-MVP-Hsp 65 mounted a strong immune response in the absence of conventional adjuvants, and could prove useful in control of fertility and the treatment of conditions/diseases where GnRH ablation is required.

Animals↗

A novel thermoacidophilic endoglucanase, Ba-EGA, from a new cellulose-degrading bacterium, Bacillus sp.AC-1.

A newly discovered bacterium, strain AC1, containing cellulase was isolated from the gastric juice of the mollusca, Ampullaria crosseans. Analysis of the 16S rDNA sequence and carbon sources revealed that the bacterium belonged to the genus Bacillus. A novel endoglucanase (Ba-EGA) was purified from culture supernatants of the bacterium growing in CMC-Na (low viscosity) induction medium. The cellulase was purified about 150-fold by ammonium sulfate fractionation, ion exchange, hydrophobic, and gel filtration chromatography, with a specific activity of 35.0 IU/mg. The molecular mass of the enzyme was 67 kDa. N-terminal amino acid sequencing revealed a sequence of SDYNYVEVLQKSILF, which had high homology with endoglucanases from the Bacillus and Clostridium species. The maximal activity of the enzyme with the substrate of CM-cellulose is at pH 4.5-6.5 and 70 degrees C, respectively. The studies on pH and temperature stability showed that the Ba-EGA is stable enough between pH 7.5 and 10.5 at 30 degrees C for 2 h, and more than 80% of the activity still remains when incubation was prolonged to 1 h at 50 degrees C. The activity of the enzyme was significantly inhibited by Fe(2+), Cu(2+) (5.0 mM of each), and sodium dodecyl sulfate (SDS) (0.5%) and obviously activated by Tween 20 and Triton X-100 (0.25% each). Binding studies revealed that the Ba-EGA had cellulose-binding domain.

Amino Acid Sequence↗

Experimental anterior lumbar interbody fusion with an osteoinductive bovine bone collagen extract.

STUDY DESIGN: A randomized experimental porcine anterior lumbar interbody fusion. OBJECTIVE: To determine the osteoinductive potential of a bovine bone derived collagen lyophilisate for anterior interbody spinal fusion in an animal model. SUMMARY OF BACKGROUND DATA: Complications associated with autologous bone graft harvesting are still major concerns when performing spinal fusion surgery. A new formulation of bovine bone collagen-protein extracts (Colloss) has been shown to be effective in animal studies as a bone graft enhancer. The present study further tested its osteogenic potential in the anterior spinal fusion cage in a controlled animal study. METHODS: Twelve normal Danish landrace pigs of 50 kg each were chosen as experimental animals. Lumbar spine interbody fusion of L3-L4, L4-L5 using titanium alloy cages was performed on each pig with pedicle screws instrumentation. Cages packed with either autograft or Colloss were randomly assigned to the two levels. Pigs were followed up to 3 months. After termination, the spine segments were evaluated by radiograph, micro-CT, and histomorphometry RESULTS: Ten pigs completed the study. Implant breakage, loosening, or spinal deformity was not observed after 12 weeks on radiograph examination. Micro-CT evaluations demonstrated that cages with Colloss had the same fusion rate (9 of 10) as those with autograft, further evaluation of bone volume (BV/TV), and trabecular thickness (Tb Th) also showed no different between them. Histologically, both autograft and Colloss levels had 80% (8 of 10) fusion rate. Histomorphometric results revealed that the only difference was the Colloss-filled cages had a higher cartilage tissue volume (P < 0.04). CONCLUSION: Colloss was effective as a bone graft substitute. It achieved the same fusion rate and the samepercentage of new bone formation as that of autologous iliac bone graft in this demanding porcine anterior spinal fusion model after 12 weeks.

Animals↗

Bone compaction enhances implant fixation in a canine gap model.

A new bone preparation technique, compaction, has increased fixation of implants inserted with exact-fit or press-fit to bone. Furthermore, a demonstrated spring-back effect of compacted bone might be of potential value in reducing the initial gaps that often exist between clinical inserted implants and bone. However, it is unknown whether the compression and breakage of trabeculae during the compaction procedure results in impaired gap-healing of compacted bone. Therefore, we compared compaction with conventional drilling in a canine gap model. Grit-blasted titanium implants (diameter 6 mm) were bilaterally inserted into cavities initially expanded to 8 mm diameters in the proximal humeri. Each dog served as its own control; thus, one humerus had the implant cavity prepared with compaction, the other with drilling. Eight dogs were euthanized after 2 weeks, and 7 dogs after 4 weeks. Humeri from additional 7 dogs represented time 0. At time 0 a spring-back effect of compacted bone was demonstrated as cavities, initially expanded to 8 mm by compaction, were reduced to a median cavity diameter of 6.6 mm. In contrast, cavities initially expanded to 8 mm by drilling, had a median cavity diameter of 8.0 mm at time 0. Compaction significantly increased all push-out parameters at 2 weeks. Compaction significantly increased peri-implant bone density at 0 and 2 weeks, and bone implant contact at 2 and 4 weeks. The faster mechanical and histological fixation with compaction indicates that the beneficial effect of reduced gap size, as compacted bone springs back, is not eliminated by an impaired gap-healing of compacted bone.

Animals↗

Effects of hyaluronan on three-dimensional microarchitecture of subchondral bone tissues in guinea pig primary osteoarthrosis.

Hyaluronan (HA) has received increasing interest as a potential agent in therapeutic intervention in osteoarthrosis (OA). HA has been shown to reduce arthritic lesions in experimental animal models of articular cartilage injury. This study was to investigate the effects of high molecular weight HA intra-articular injection on subchondral bone tissues. Fifty-six male guinea pigs were randomly divided into 5 groups. During the initial 2.5-month period, three groups received intra-articular injection of HA 0.4 mg/kg/week for 5 weeks in both knee joints. Two control groups received vehicle. After 2.5 months, one HA group and one control group were sacrificed. The remaining 3 groups (5.5-month groups) were left for an additional 3 months before sacrifice during which time one HA group received additional 5 weeks injections, one HA group received no more injections, and the control group received vehicle. The left tibiae were harvested and micro-CT scanned to quantify three-dimensional microarchitecture of subchondral bone plate, cancellous bone and cortical bone, followed by mechanical testing and collagen and mineral determinations. All HA-treated groups had almost normal cartilage, whereas the control groups had typical OA-related cartilage degradation. In the 2.5-month group, HA resulted in significantly decreased subchondral plate volume fraction and thickness and HA-treated cancellous bone had significantly lower bone volume fraction, and typical rod-like structure. After 5.5 months, these changes were more pronounced, with an additional marked decrease in connectivity and bone surface density. HA-treated cortical bone had significantly greater volume fraction at both observation times. HA groups had greater bone mineral concentration and reduced collagen to mineral ratio with similar mechanical properties of cancellous bone but less stiff cortical bone. The effects of HA on cartilage and subchondral bone were maintained when treatment was discontinued. In summary, HA effectively protects against cartilage degeneration, decreases subchondral bone density and thickness, changes trabecular structure toward rod-like, so that subchondral bone becomes more compliant and thereby reduces cartilage stress during impact loading. HA preserved cancellous bone mechanical properties by increasing bone mineralization. Early HA administration is effective for intervention of OA initiation and progression, and short-term early HA treatment is sufficient to maintain treatment effects.

Animals↗

Purification and characterization of two endo-beta-1,4-glucanases from mollusca, Ampullaria crossean.

Two novel endo-beta-1,4-glucanases, EG45 and EG27, were isolated from the gastric juice of mollusca, Ampullaria crossean, by anion exchange, hydrophobic interaction, gel filtration and a second round of anion exchange chromatography. The purified proteins EG45 and EG27 appeared as a single band on sodium dodecylsulfate polyacrylamide gel electrophoresis with a molecular mass of 45 kDa and 27 kDa, respectively. The optimum pH for CMC activity was 5.5 for EG45 and 4.4-4.8 for EG27. The optimum temperature range for EG27 was broad, between 50 degrees and 60 degrees; for EG45 it was 50 degrees. The analysis on the stability of these two endo-beta-1,4-glucanases showed that EG27 was acceptably stable at pH 3.0-11.0 even when the incubation time was prolonged to 24 h at 30 degrees, whereas EG45 remained relatively stable at pH 5.0-8.0. About 85% of the activity of EG27 could be retained upon incubation at 60 degrees for 24 h. However, less than 10% residual activity of EG45 was detected at 50 degrees. Among different kinds of substrates, both enzymes showed a high preference for carboxymethyl cellulose. EG45, in particular, showed a carboxymethyl cellulose hydrolytic activity of 146.5 IU/mg protein. Both enzymes showed low activities to xylan (from oat spelt) and Sigmacell 101, and they were inactive to p-nitrophenyl-beta-D-cellobioside, salicin and starch.

Animals↗

[Research of microbio-remediation of oil-contaminated wetland in Liaodong Bay].

To investigate the effect of microbes on oil degradation, we use the method of introducing selected bacteria to the soil samples. Experiment shows that the combined bacteria are preferable to the single ones because of their synergetic functions. The optimum condition for oil degradation was controlled at pH 8.0, 25 degrees C. Some surfactants are helpful to breed bacteria, thus improves the oil degradation. After adding TW-80 (300 mg x kg(-1)) for 8 days, the number of bacteria was amplified 6.22 times and the oil degradation rate was enlarged 20.1%. Adequate amount of H2O2 is beneficial for microbes to decompose oil, but its overdose may slay bacteria. 400 mg x L(-1) H2O2 each time is suitable dose. In 11 days after 7 000 mg x L(-1) H2O2 was added entirely, the oil degradation rate rose greatly from 39.81% (without H2O2) up to 66.79%.

Acinetobacter↗

The immunogenicity of recombinant and dimeric gonadotrophin-releasing hormone vaccines incorporating a T-helper epitope and GnRH or repeated GnRH units.

In this study, we designed two linear peptides, GnRH-hinge-MVP, which consists of human gonadotrophin-releasing hormone (GnRH), hinge fragment 225-232/225'-232' of human IgG1 and a T helper peptide from measles virus protein (MVP), and GnRH3-hinge-MVP, which contains three copies of GnRH (so termed GnRH3). The DNA constructs encoding for the two peptides were fused to the C-terminal encoding sequence of asparaginase, encompassing residues 199-326, through an acid-labile aspartyl-prolyl linker. The chimeric genes were expressed at high levels in Escherichia coli. The fusion proteins were purified to approximate homogeneity by means of washing the inclusion bodies and by ethanol precipitation. The GnRH-hinge-MVP or the GnRH3-hinge-MVP was released from the fusion proteins by cleavage with hydrochloric acid and further oxidized into double-chain miniproteins after purification. Both dimeric constructs proved to be efficient immunogens. It was shown that rats immunized with the immunogens generated antibodies specific for GnRH. The dimeric GnRH3-hinge-MVP containing three copies of GnRH in each chain induced a higher titre of anti-GnRH antibodies than the GnRH-hinge-MVP, containing a single copy of GnRH in each chain. These results demonstrate that combining multicopies or single copies of peptide with hinge fragment of human IgG and T helper peptide from measles virus protein can induce anti-peptide immune responses. Our data also suggest that these methods of preparation and dimerization of the recombinant polypeptides may provide a useful strategy for other polypeptide vaccine developments.

Amino Acid Sequence↗

Persistent HIV type 1 infection in semen and blood compartments in patients after long-term potent antiretroviral therapy.

HIV-1 RNA levels in semen and blood compartments decrease below detection limits during highly active antiretroviral therapy. Despite these therapeutic effects, it is clear that persistent, latent HIV-1 reservoirs are capable of rebounding in the absence of drug treatment or by evolution of escape mutants remain. The current study was designed to examine the presence of latent virus in semen and blood compartments and its evolution following potent combination therapy with indinavir (protease inhibitor) and efavirenz [nonnucleoside reverse transcriptase (RT) inhibitor]. Using an ultrasensitive in situ hybridization assay HIV-1 mRNA was detected in cultured seminal and blood mononuclear cells in all patients up to 1789 days posttherapy. Higher levels of HIV-1 mRNA were consistently detected in seminal mononuclear cells as compared to peripheral blood mononuclear cells (PBMC) in all time points analyzed posttherapy. Analysis of viral RNA from cultured PBMC before and after therapy displayed no evidence of therapy-induced drug resistance in the viral polymerase gene in the majority of patients. However, distinct envelope populations were detected in these viral RNA populations following therapy, indicating possible selection of quasispecies. The observed ongoing replication and evolution in the PBMC viral envelope sequences likely occurred in the seminal compartment HIV populations, given that the seminal cells showed the ability to express HIV-1 mRNA following cultivation. This together with our previous studies (Gupta P, et al.: J Infect Dis 2000;182:79-87) suggest that the genital and blood compartments likely serve as distinct reservoirs harboring latent HIV-1 during prolonged drug therapy.

Alkynes↗

pH-dependent stability of EGX, a multi-functional cellulase from mollusca, Ampullaria crossean.

The cellulase activity and stability of EGX, a multi-functional cellulase previously purified from the mollusca Ampullaria crossean, was systematically studied under different pH. The pH induced con-formation and stability change of EGX have been investigated by using the intrinsic fluorescence, ANS fluorescence and CD spectrum. It has been found that the conformation and activity of this cellulase were strongly dependent on the pH. EGX was stable for both the enzyme activity and the conformation from pH 5.6 to pH 7.4. As shown by intrinsic and ANS fluorescence, no red shift of emission maximum occurred and a negligible intensity change was observed at pH 5.6-7.4. The activity of EGX remained about 80% in pH 5.6-7.4 and obviously decreased out of side the pH range. Urea-induced changes in EGX at pH 5.4 and pH 8.0 were measured by intrinsic fluorescence and CD spectrum. At pH 5.4, a significantly red shift of emission maximum occurred when the concentration of urea was 5 M compared to the concentration was 3 M at pH 8.0. The alpha-helix at pH 5.4 was 40.51% in the absence of urea and 31.04% in the presence of 4 M urea. At pH 8.0 the alpha-helix was 7.23% in the presence of 4 M urea. The data indicated that EGX was much susceptible to urea-induced unfolding at pH 8.0 and much stable at pH 5.4. The greater pH dependent stability of EGX may allow the enzyme to adequately catalyze the hydrolysis of cellulosic materials under natural or industrial extreme conditions.

Animals↗

A monovalent anion affected multi-functional cellulase EGX from the mollusca, Ampullaria crossean.

A cellulose hydrolytic enzyme was isolated from the stomach juice of Ampullaria crossean, a kind of herbivorous mollusca. The enzyme was purified 45.3-fold to homogenety by ammonium sulfate precipitation, DEAE-Sephadex A-50 column, Bio-gel P-100 gel filtration column, and phenyl-Sepharose CL-4B column chromatography. The enzyme was designated as cellulase EGX. The purified enzyme is a multi-functional enzyme with the activities of exo-beta-1,4-glucanase (14.84 U/mg for p-nitrophenyl beta-D-cellobioside), endo-beta-1,4-glucanase (40.3 U/mg for carboxymethyl cellulose), and endo-beta-1,4-xylanase (196 U/mg for soluble xylan from birchwood). The monovalent anions such as F(-), Cl(-), Br(-), I(-), and NO(3)(-) are essential for its exo-beta-1,4-glucanase activity but have no effect on the activity for xylan, while I(-) higher than 5mM would inhibit the exo-beta-1,4-glucanase activity. The monovalent anions Cl(-) and Br(-) activate its endo-beta-1,4-glucanase activity. Binding of Cl(-) enhances the thermostability of EGX, but does not affect its fluorescence emission spectrum. The molecular mass of EGX is 41.5 kDa, as determined by SDS-PAGE. The pI value is about pH 7.35. The xylan hydrolytic activity of EGX reaches to the maximum between pH 4.8 and 6.0 and the pNPC hydrolytic activity reaches the maximum between pH 4.8 and 5.6, while that for CMC hydrolytic activity is between pH 4.4 and 4.8. Preliminary results showed that the enzyme was secreted by the mollusca itself.

Ammonium Sulfate↗

Compacted cancellous bone has a spring-back effect.

A new surgical technique, compaction, has been shown to improve implant fixation. It has been speculated that the enhanced implant fixation with compaction could be due to a spring-back effect of compacted bone. However, such an effect has yet to be shown. Therefore we investigated in a canine model whether implant cavities prepared with compaction had spring back. Before killing the animals, we used one of two surgical techniques to make implant cavities of identical dimensions in both lateral femoral condyles of 7 dogs. One side had the implant cavity prepared with compaction, the other side with drilling. The cavities were left empty in vivo for 10 minutes before the dogs were killed. Postoperative micro-CT scanning showed that the diameters of the compacted cavities were significantly smaller than those of the drilled cavities, although they had had identical dimensions initially. Thus we found a spring-back effect of compacted bone, which may be important for increasing implant fixation by reducing initial gaps between the implant and bone.

Animals↗

Isolation of a multi-functional endogenous cellulase gene from mollusc, Ampullaria crossean.

The cellulase genes of some animals, most coding for endo-beta-1,4-glucanases, were found and cloned. There has been no reports about genes encoding exo-beta-1,4-glucanase or endo- -1,4-xylanase from animal. Here we cloned the cDNA of a cellulase designated as EGX from mollusc, Ampullaria crossean, and expressed it in Pichia pastoris for the first time. The cellulase EGX is a multi-functional beta cellulase with the activities of exo-beta-1,4-glucanase, endo-beta-1,4-glucanase and endo-beta-1,4-xylanase. The opening reading frame of EGX cDNA is 1185 bp and encodes 395 amino acids. The EGX gene can also be amplificated from the genomic DNA by PCR, which verified the endogenous origin of this gene. This EGX gene was the first multi-functional cellulase gene that was directly isolated from animals.

Amino Acid Sequence↗

[Distribution of the HIV/AIDS associated CCR5Delta32,CCR2b-64I,SDF1-3'A allelesin Chinese Dai and Chingpaw populations from Dehong autonomous prefecture of Yunnan Province].

The purpose of the work is to investigate the frequencies and polymorphisms of HIV-1 resistant CCR5delta32,CCR2b-64I,SDF1-3'A alleles in Chinese Dai and Chingpaw populations. Whole blood samples from 101 Dai subjects and 113 Chingpaw were collected randomly and their genomic DNA were extracted with QIAgen Blood Kits. Allelic frequencies were identified by PCR-RFLP analysis. Allelic polymorphisms in Dai population or Chingpaw population and both sexes in the samples were analyzed by chi(2) test. The frequencies of CCR5delta32,CCR2b-64I,SDF1-3'A alleles in Dai population were 0.0000,0.2130,0.2030, respectively. The frequencies of CCR5delta32,CCR2b-64I,SDF1-3'A alleles in Chingpaw population were 0.000, 0.1637, 0.1770, respectively. Distributions of the CCR2b-64I,SDF1-3'A alleles among the both populations were in accordance with Hardy-Weinberg equilibrium. No statistical difference was found in the allelic frequencies of both CCR2b-64I and SDF1-3'A between male and female individuals. The frequencies of CCR5delta32,CCR2b-64I alleles in Chinese Dai and Chingpaw populations are similar to that in Chinese Han population, while the frequency of SDF1-3'A allele in Chinese Dai and Chingpaw populations are lower in contrast to that in Chinese Han population. The genotyping and polymorphism of CCR5delta32,CCR2b-64I,SDF1-3'A alleles in Chinese Dai and Chingpaw populations of Yunnan Province are the first time studied in China. The significance of the three mutant alleles conferring genetic resistance to HIV-1 and AIDS progression remains to be clarified.

English Abstract↗