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Haplotype diversity and linkage disequilibrium at human G6PD: recent origin of alleles that confer malarial resistance.

The frequencies of low-activity alleles of glucose-6-phosphate dehydrogenase in humans are highly correlated with the prevalence of malaria. These "deficiency" alleles are thought to provide reduced risk from infection by the Plasmodium parasite and are maintained at high frequency despite the hemopathologies that they cause. Haplotype analysis of "A-" and "Med" mutations at this locus indicates that they have evolved independently and have increased in frequency at a rate that is too rapid to be explained by random genetic drift. Statistical modeling indicates that the A- allele arose within …

HLA class II alleles associated with susceptibility and resistance to Crohn's disease in the Jewish population.

Previous studies have suggested that susceptibility to Crohn's disease (CD) is associated with the histocompatibility complex (HLA) class II alleles DR1, DQ5, and DR13 in the Caucasian population, DR7 in the French and German populations, and DR4 and DQ4 in the Japanese population. However, little is known about the relationship between HLA class II alleles and CD in the Jewish population since these previous studies included few Jewish individuals. In order to determine whether the HLA associations observed with predominantly non-Jewish populations were also present in the Jewish CD populatio…

Association analysis between the MIC-A and HLA-B alleles in Japanese patients with Behçet's disease.

OBJECTIVE: Behçet's disease is known to be strongly associated with HLA-B51 in many different ethnic groups. Recently, by association analysis using refined microsatellite mapping, the critical region for Behçet's disease was identified as a 46-kb segment centromeric to the HLA-B gene. No expressed gene has been detected in this segment to date except the MIC-A (major histocompatibility complex class I chain-related gene A) and HLA-B genes. The present study was undertaken to analyze allelic distribution of the MIC-A gene among Japanese patients with Behçet's disease. METHODS: Ninety-five Jap

Four new DP alleles identified in a study of 500 unrelated bone marrow donor-recipient pairs.

HLA-DP genotyping of 500 donor recipient pairs in a retrospective analysis sponsored by the National Marrow Donor Program (NMDP) identified four new DP alleles, two DPB1 and two DPA1. DNA sequencing confirmed that DPB1*8001 and *8101, each found in a single individual, are novel combinations of previously described sequence motifs in the six variable regions of DPB1. DPA1*02014, found in two individuals, is identical to DPA1*02011 except for a novel silent substitution, a G to A transition at the third position of codon 14. DPA1*01032, found in one individual, is identical to DPB1*01031 except…

Те же аллели HLA-DQ определяют либо подверженность, либо устойчивость к различным аутоиммунным заболеваниям, вызываемым коксакевирусом.

Важной характеристикой аутоиммунных заболеваний является их связь с основными гистосопоставимыми сложными классами I и II. В этом исследовании мы сравнили сахарный диабет, зависящий от инсулина (IDDM), с идиопатической дилапсированной кардиомиопатией (IDC) с сугубо иммунологической точки зрения. Хотя органы-объекты отличаются друг от друга, будучи в одном случае бета-клетками поджелудочной железы, производящими инсулин, а в другом - миокитами сердца, многие аспекты иммунного разрушения конкретных тканей являются распространенными. Схожие, но различные штаммы Коксакивируса В с панкреотропной ил

Совпадение в аннотации оригинала
An important characteristic of autoimmune diseases is their association with major histocompatibility complex class I and class II alleles. In this study, we compared insulin-dependent diabetes mellitus (IDDM) with idiopathic dilated cardiomyopathy (IDC) from a strictly immunologic perspective. Although the target organs are different, being in one case the …

Role of HLA-B and C alleles in development of psoriasis in patients from North India.

The association of HLA antigens with susceptibility for development of psoriasis vulgaris has been studied mostly using serologic methods. A number of different HLA class I antigens have been reported to be associated with predisposition to develop this disease. While Cw6 is the allele most commonly thought to confer risk for psoriasis, a number of HLA-B locus alleles have also been thought to be involved and, recently, in at least three studies, a specific amino acid in the HLA-C heavy chain has been implicated. With the recent development of molecular methods for typing for HLA class I allel…

papG alleles of Escherichia coli strains causing first-episode or recurrent acute cystitis in adult women.

The distribution of the three alleles of the P adhesin gene papG (classes I-III) was assessed among 74 Escherichia coli urine isolates from women with first-episode or recurrent cystitis, and papG genotype was compared with clinical origin, O serogroup, agglutination of Gal(alpha1-4)Gal-coated latex beads and human or sheep erythrocytes, and hemolysin production. The class-III-only papG genotype (27% of strains) predominated over the I + III (3%) and II-only (7%) genotypes, irrespective of clinical category. In contrast to the class II papG allele, the class III allele was significantly concen…

The frequency of hemochromatosis-associated alleles is increased in British patients with sporadic porphyria cutanea tarda.

The cause of the hepatic siderosis and iron overload that is common in porphyria cutanea tarda (PCT) is uncertain. Heterozygosity for geneti … s in 41 British patients with sporadic PCT. Fifteen patients carried the hemochromatosis-associated alleles D6S265-1 and D6S105-8. Four of these were homozygous for the ancestral haplotype D6S265-1 : D6S105-8: D6S1260-4. We estimate that approximately 37% of British patients with sporadic PCT carry at least one hemochromatosis gene compared with 10% of th …

Six new DPB1 alleles identified in a study of 1,302 unrelated bone marrow donor-recipient pairs.

Six new DPB1 alleles were identified by PCR-SSOP methodologies in the course of a retrospective study of the role of HLA matching in the outcome of unrelated donor bone marrow transplantation. Sequencing confirmed that five of these alleles (DPB1*5901, *6801, *7101, *7201, and *7301) represent novel combinations of previously described sequence motifs in the variable regions of DPB1; the sixth (DPB1*7001) appears to result from a novel point mutation. These data support previous observations which suggest that multiple mechanisms, including segmental exchange and mutation, appear to be respons…

D4 dopamine-receptor (DRD4) alleles and novelty seeking in substance-dependent, personality-disorder, and control subjects.

Two reports have been published suggesting an association between the personality trait of novelty seeking and the DRD4*7R allele at the D4 … subjects heterozygous for a null mutation did not differ from that of subjects with two functional alleles. We conclude that the most likely explanation of these results is that the DRD4 VNTR does not influence directly the trait of novelty seeking, in these samples.

Exclusive development of T cell neoplasms in mice transplanted with bone marrow expressing activated Notch alleles.

Notch is a highly conserved transmembrane protein that is involved in cell fate decisions and is found in organisms ranging from Drosophila to humans. A human homologue of Notch, TAN1, was initially identified at the chromosomal breakpoint of a subset of T-cell lymphoblastic leukemias/lymphomas containing a t(7;9) chromosomal translocation; however, its role in oncogenesis has been unclear. Using a bone marrow reconstitution assay with cells containing retrovirally transduced TAN1 alleles, we analyzed the oncogenic potential of both nuclear and extranuclear forms of truncated TAN1 in hematopoi…

Selection against mutant alleles in blood leukocytes is a consistent feature in Incontinentia Pigmenti type 2.

Incontinentia Pigmenti 2 (IP2) is an X-linked dominant disorder with male lethality. Affected females display a characteristic skin eruption that evolves through four classic stages, frequently accompanied by dental and retinal abnormalities. Non-random (skewed) X-inactivation in peripheral blood leukocytes and in fibroblasts has been observed in females with IP2; however, sample sizes have been small and methods of analysis varied. We have examined X-inactivation in a large group of multigenerational IP2 families, in smaller families, and in isolated cases. Ninety-eight percent of affected fe

T-cell receptor BV6S1 null alleles and HLA-DR1 haplotypes in polyarticular outcome juvenile rheumatoid arthritis.

JRA is a complex of disease subtypes which are normally identified by clinical features such as age of onset and extent of joint involvement … association considerably. This implies that there is an increased genetic load defined by specific alleles of both MHC and TCR genes.

Apparent segregation of null alleles ascribed to deletions of the ornithine transcarbamylase gene in congenital hyperammonaemia.

Ornithine transcarbamylase (OTC) deficiency is an X-linked disorder of the urea cycle mapped to chromosome Xp21.1. Here, we show that apparent segregation of null alleles at the OTC locus and flanking polymorphic loci mimicked false maternity or false paternity in three affected families. Based on these observations, we suggest giving consideration to gene deletion when dealing with segregation of null alleles in OTC deficiency.

Genetic influences on bone density: physiological correlates of vitamin D receptor gene alleles in premenopausal women.

Common vitamin D receptor (VDR) gene alleles have recently been shown to contribute to the genetic variability in bone mass and bone turnover, however, the physiological mechanisms involved are unknown. To examine this, the response to 7 days of 2 micrograms oral 1,25-dihydroxyvitamin D[1,25-(OH)2D] (calcitriol) stimulation was assessed in 21 premenopausal women, homozygous for one or other of the common VDR alleles (bb, n = 11; BB, n = 10). Indices of bone turnover and calcium homeostasis were measured during 2 weeks. Baseline osteocalcin, 1,25-(OH)2D, type I collagen carboxyterminal telopept…

D2 dopamine receptor alleles do not influence severity of Tourette's syndrome. Results from four large kindreds.

OBJECTIVE: We investigated the recently proposed hypothesis that the A1 allele of the Taq I polymorphic system at the D2 dopamine receptor gene (DRD2) influences the severity of Tourette's syndrome (TS). We have previously demonstrated that DRD2 is not linked to TS, establishing that it cannot be the major locus determining the susceptibility to develop TS. METHOD: We studied alleles at the DRD2 A system in patients with TS or chronic multiple tics in four extended kindreds segregating TS. If this allelic system at DRD2 is associated with severity of TS, then among affected family members, th…

HLA-D alleles associated with generalized disease, localized disease, and putative immunity in Onchocerca volvulus infection.

Human infections with the tissue nematode Onchocerca volvulus result in a variety of clinical conditions that possibly include protective immunity. In a West African area hyperendemic for human onchocerciasis, 120 residents were classified according to clinical and laboratory findings as presenting with generalized onchocerciasis, localized onchocerciasis, or as being putatively immune. The three groups differed in the distribution of HLA-D variants as determined by DNA typing. The most pronounced differences were found among alleles of the DQ loci. The haplotype DQA1*0501-DQB1*0301 was signif…

Susceptible and protective major histocompatibility complex class II alleles in early-onset pauciarticular juvenile chronic arthritis.

Oligonucleotide typing for alleles of the MHC loci DRB1, DQA1, and DQB1 was performed in 160 patients suffering from EOPA, JCA (or JRA = juvenile rheumatoid arthritis). Allele and haplotype frequencies of the patients were compared with the data of an unrelated healthy control group consisting of 200 individuals. Analysis of frequencies shows that HLA alleles are associated not only with susceptibility to EOPA-JCA but also with protection from the disease. The presence of protection connected with certain HLA alleles was assessed using a calculation which takes into account the condition that …

No association with HLA class II alleles in Swedish patients with cutaneous manifestations of Lyme borreliosis.

The possibility of an association between manifestations of Lyme borreliosis and HLA class II alleles has been investigated with varying results. In the present study, we used genomic typing techniques to determine the DR, DQ and DP allele frequencies in 29 patients with erythema migrans and 36 patients with acrodermatitis chronica atrophicans. We did not find a significant deviation from controls in the distribution of the HLA class II alleles in any of these disease manifestations, nor in the subgroup of 8 patients with acrodermatitis chronica atrophicans and long-standing arthritis. With th…

Human leukocyte antigen alleles and haplotypes associated with selective immunoglobulin A deficiency in Spanish pediatric patients.

Class I and II human leukocyte antigens were determined by a standard microlymphocytotoxity test in a group of 45 pediatric patients with se … study confirms some of the previous findings in other white populations and describes new possible alleles and haplotypes that could be implicated with IgA-D susceptibility and resistance.