To investigate the genetic factors in Koreans with leprosy, 157 unrelated leprosy patients have been typed for HLA antigens, and compared with 162 healthy controls. The patient group consisted of 124 with lepromatous leprosy and 33 with tuberculoid leprosy. HLA-A11 was found to be increased in lepromatous leprosy (p=0.0005). HLA-Aw33 was found to be increased in both lepromatous leprosy (p = 0.0002) and tuberculoid leprosy (p = 0.005). HLA-Cw5 was found to be decreased in lepromatous leprosy (p = 0.009). Frequencied of HLA-B antigens did not differ significantly between the leprosy patients and the healthy controls.
HLA Antigens/analysis* ; Human ; Korea ; Leprosy/genetics ; Leprosy/immunology* ; Phenotype

OBJECTIVEMultiple locus variable number-tandem repeat (VNTR) analysis (MLVA) had been proposed as a means of strain typing for tracking of source and studying the transmission chain of pathogens. However, empirical data for a defined population from scale and duration were lacking for studying the transmission chain of leprosy.

METHODSMLVA on 7 VNTR loci was applied to the strain typing on prevalent Mycobacterium leprae isolates collected from Qiubei county, Yunnan province during 2002-2006 in the study on the relationship between geographic distribution and genotypes of M. leprae. The strain typing, combined with conventional epidemiological investigation was performed to trace the transmission chain.

RESULTS(1) Phylogenetic analyses through application of PAUP 4.0, The M. leprae were grouped into A, B, C, D and E strains according to the allelic range 9, 11-13, 15-26 and > 26 on the GTA9 locus. The strains with 9 copies on GTA9 locus, was named A. (2) Genotypes of strains from the five multi-case families located at North and North-West parts were similar and belonged to A strains. VNTR patterns of intra-family were identical or similar but not identical inter-family. (3) Not only A cluster appeared higher proportion in total isolates but also distributes cluster, indicating ongoing transmission from recent findings.

CONCLUSIONVNTR strain typing was suitable to trace the short chain of transmission in both small area and intra-families. Multi-case families might constitute epidemic foci and source of M. leprae in villages, causing the predominant strain or cluster which tends to be those identified in multi-case families and resulted in the spreading of leprosy. A long-term study was underway to reveal whether A strain was predominant strain and to observe the evolution of M. leprae in this spatially and temporally defined endemic population.

Female ; Genotype ; Humans ; Leprosy ; microbiology ; Male ; Minisatellite Repeats ; genetics ; Molecular Epidemiology ; Mycobacterium leprae ; classification ; genetics ; Phylogeny ; Polymerase Chain Reaction

Adult ; Female ; Heat-Shock Proteins ; genetics ; Humans ; Leprosy ; diagnosis ; genetics ; microbiology ; Male ; Middle Aged ; Mycobacterium leprae ; pathogenicity ; Polymerase Chain Reaction ; methods ; Polymorphism, Restriction Fragment Length ; Skin ; metabolism

OBJECTIVETo understand the genotypic mapping of Mycobacterium leprae identified in China and to compare with those from other countries to select suitable alleles for epidemiological investigation in the transmission chain of leprosy.

METHODSVarious number of tandem repeat(VNTR) in genomic DNA of Mycobacterium leprae was used in the present genotyping study. 33 skin biopsies from Wenshan prefecture,Yunnan province and 17 from other parts of China were studied. DNA extracted from skin biopsies of leprosy patients was subjected to PCR followed by agarose gel analysis and DNA sequencing to determine the number of repeats.

RESULTSLoci GGT-5,12-5,21-3 and 23-3 were as highly homogenous as 100%; The homogeneity of loci AC-8, 18-8, 27-5 and rpoT were 97%, 94%, 97% and 85% respectively. Loci GTA-9, AC-9 and 6-7 showed significant allelic diversity in isolates and the diversity of GTA-9 in Mycobacterium leprae isolated from China was also different from those identified other countries. We had subjected loci GTA-9 and the ten loci to phylogenetic tree analysis respectively.

CONCLUSIONThe present study revealed that the genotype of Mycobacterium leprae identified from China was close to the strains from the Philippines and India although a few loci were somehow differentiate. Locus 12-5 manifested as only 3 copies in China whereas 4-5 copies predominating in other countries. 12-5 locus might serve as a useful marker to diffrentiate Chinese strains from those in other countries. However, further study on the diversity of GTA-9 was needed in China. The molecular typing of Mycobacterium leprae from different geographic areas might be useful in studying the transmission of leprosy.

Alleles ; China ; epidemiology ; DNA, Bacterial ; Genotype ; Humans ; Leprosy ; epidemiology ; transmission ; Molecular Epidemiology ; Mycobacterium leprae ; genetics ; isolation & purification ; Polymerase Chain Reaction ; Skin ; microbiology