Human immunoglobulin constant heavy G chain (IGHG) (Fcγ) (GM) genes, defining innate variants of IgG molecules and B cells, have impact on disease and therapy.

The distinguished alternative GM allotypes localized in immunoglobulin constant heavy G chain IGHG (Fcγ) (GM) genes on chromosome 14q32.3 define two unique variants of respectively IgG3, IgG1 and IgG2 subclasses, with different structures and functions. The IGHG allele (allotypes), expressed in homozygous or heterozygous forms, are assessed by new serological methods. Fixed combinations of γ3, γ1 and γ2 allotypes constitute the haplotypes, which are indirect markers of B cells. We highlight the role of homozygous IGHG genes with restricted qualities of IgG subclass molecules and B cells. These common Mendelian IGHG genes respond differently to allergens and infections, both bacterial and viral, and to active and passive immunotherapies. IGHG genes have an impact on diseases such as allergy, immunodeficiency, autoimmunity and malignancy. Association/linkage of different IGHG genes gives information about risk/protection, good or bad prognosis, for improvement of clinical care. The IGHG gene map of healthy Caucasians is registered

Immunoglobulin Allotypes and Immune Response to Meningococcal Group B Polysaccharide

Serum samples were collected from 120 healthy adult volunteers (105 Caucasians and 15 Negros) before and after immunization with meningococcal polysaccharide (MPS) group B vaccine. Antibodies to MPS group B were measured and sera were typed for several Gm and Km(l) allotypes. A significant association was found between the Km(l) allotype and immune response to MPS group B in Caucasians

Immunoglobulin G Heavy Chain (Gm) Allotypes in Multiple Sclerosis

Serum samples from 70 Caucasian patients with multiple sclerosis were typed for nine Gm markers. Significant association was found with the Gm 1,17;21 phenotype, and the relative risk for individuals with this phenotype was calculated at 3.6. The data indicate that Caucasians positive for Gm 1,17;21 are almost four times more likely to develop multiple sclerosis than those without this phenotype

Heterozygosity at Gm Loci Associated with Humoral Immunity to Osteosarcoma

Familial clustering of osteosarcoma suggests the involvement of genetic factors (1, 2), and the demonstration of a high incidence of osteosarcoma-specific antibodies (3, 4), as well as tumor-specific cell-mediated immunity (5) in patients and their relatives, indicates the involvement of immunological factors in the pathogenesis of this disease. Certain Gm allotypes (genetic markers of IgG) have been shown to be associated with a high relative risk of some forms of cancer. For instance, in Caucasians an unusual Gm haplotype--Gm 1,3;5,13,14--has been found to be associated with neuroblastoma (6), and an increased frequency of Gm (2) has been reported in patients with malignant melanoma (7, 8). A recent report has shown an association of the Gm 1,2; 13,15,16,21 phenotype with lung cancer and primary hepatoma in the Japanese (9). To our knowledge, however, the possible role of Gm allotypes in predisposition to osteosarcoma has not been examined. Immune responsiveness to a variety of antigens in both experimental animals and humans has been shown to be controlled either by major histocompatibility complex (MHC)-linked immune response (Ir) genes or by allotype-linked Ir genes (10-13). In some instances an interactive effect of these two unlinked genetic systems has been observed (12). It is possible that MHC-linked or allotype-linked Ir genes may also influence humoral immunity to tumor antigens. In this report we present evidence for complementary Ir genes controlling immune responses to osteosarcoma-associated antigens (OSAA)

Response to Immunization with Haemophilus influenzae Type b Polysaccharide-Pertussis Vaccine and Risk of Haemophilus Meningitis in Children with the Km(1) Immunoglobulin Allotype

In experimental animals, immune responses to certain antigens are regulated by immunoglobulin allotype-linked genes. In an effort to detect such genes in humans, we examined the antibody responses of 74 healthy children with different Km(l) or Gm(23) allotypes to a Haemophilus influenzae type b vaccine (type b polysaccharide capsule-pertussis vaccine). The anticapsular antibody responses of black or white children with the Km(1) allotype were 4.6- to 9.5-fold higher than those of children who lacked this determinant (P \u3c 0.004). No significant differences were found in antibody response with respect to the Gm(23) allotype. The frequencies of Km(l) and Gm(23) also were examined in 170 patients with Haemophilus meningitis, 71 patients with epiglottitis, and 173 control children. Km(1) was detected less frequently in black patients with meningitis (38%) than in those with epiglottitis (81%, P \u3c 0.002) or in controls (66%, P \u3c 0.0007). The relative risk of meningitis thus was 3.2-fold lower among black children with the Km(1) allotype than in those who lacked this allotype (odds ratio = 0.3, 95% confidence interval 0.2 to 0.6). However, the risk of meningitis was not decreased in white children with the Km(l) allotype (odds ratio = 1.0). There were no significant differences in the frequency of Gm(23) among the patient groups and controls. The Km(l) allotype but not the Gm(23) thus defines a subpopulation of children of both races who are high responders to this vaccine, and black children but not white children with the Km(l) allotype are at decreased risk of developing Haemophilus meningitis. These data indicate that in blacks, genes associated with Km(l) may affect immune response to a prototype type b Haemophilus vaccine, and perhaps interact with another factor related to race to affect susceptibility to Haemophilus meningitis

Immunoglobulin κ Chain Allotypes (KM) in Onchocerciasis

GM and KM allotypes, powerful tools for genetic characterization of human populations, have been shown to play an important role in genetic predisposition to some infectious diseases. Two diverse racial groups-Afro-Ecuadorians and Amerindians-living in a single restricted geographical area of Ecuador, appear to have different risk factors for acquisition and clinical expression of onchocerciasis, a disease caused by the filarial parasite Onchocerca volvulus. In this study, GM and KM allotypes were determined in 25 Afro-Ecuadorians and 24 Amerindians infected with Onchocerca volvulus (INF) and in putative immune individuals (PI). In Afro-Ecuadorians, the frequency of the homozygous KM 3 phenotype was significantly decreased in INF as compared with the PI group (20 vs. 68%; P = 0.0012), while the frequency of the heterozygous KM 1,3 phenotype was increased in INF as compared with the PI subjects (48 vs 9%; P = 0.0044). These results suggest that in Afro- Ecuadorians KM 3 is associated with a lower relative risk (resistance), whereas KM 1,3 is associated with an increased risk (susceptibility) of onchocerciasis

Improving fertilizer recommendations for Nepalese farmers with the help of soil-testing mobile van

Smallholder farmers dominate agriculture in Nepal. These farmers have poor knowledge about agriculture and lack of support for soil management and integrated plant-nutrient systems. Focusing on the importance and need for soil-fertility management, a soil-testing mobile van program has recently been introduced in Nepal by Soil Management Directorate, Hariharbhawan. With the introduction of the mobile lab, famers can get their soil tested for nutrient deficiencies and fertilizer requirements at their doorsteps. Using mobile lab, spatial distributions of chemical properties, including pH, organic matter (OM), total nitrogen (N), available phosphorus (as P2O5), and available potassium (as K2O) were examined in soil samples taken from the 0 to 15 cm depth from selected agricultural fields in eight different districts in the mid-hills and Terai regions of Nepal. Tests conducted on 1,479 soil samples in the soil-testing mobile van revealed the following: the mean soil OM ranged from 0.01 to 1.77%; total N content ranged from 0.01 to 0.08%; mean available P2O5 ranged from 16.47 to 197.82 kg ha−1; and mean available K2O ranged from 84.3 to 422.57 kg ha−1. For each crop to be grown, farmers were provided with individual soil health reports and fertilizer recommendations (rate, amount, and type). This program not only allows scientists and farmers to work closely and share information but also serves as a model for the nation to successfully transfer technology for improving soil health and sustainability

Improving fertilizer recommendations for Nepalese farmers with the help of soil-testing mobile van

Smallholder farmers dominate agriculture in Nepal. These farmers have poor knowledge about agriculture and lack of support for soil management and integrated plant-nutrient systems. Focusing on the importance and need for soil-fertility management, a soil-testing mobile van program has recently been introduced in Nepal by Soil Management Directorate, Hariharbhawan. With the introduction of the mobile lab, famers can get their soil tested for nutrient deficiencies and fertilizer requirements at their doorsteps. Using mobile lab, spatial distributions of chemical properties, including pH, organic matter (OM), total nitrogen (N), available phosphorus (as P2O5), and available potassium (as K2O) were examined in soil samples taken from the 0 to 15 cm depth from selected agricultural fields in eight different districts in the mid-hills and Terai regions of Nepal. Tests conducted on 1,479 soil samples in the soil-testing mobile van revealed the following: the mean soil OM ranged from 0.01 to 1.77%; total N content ranged from 0.01 to 0.08%; mean available P2O5 ranged from 16.47 to 197.82 kg ha−1; and mean available K2O ranged from 84.3 to 422.57 kg ha−1. For each crop to be grown, farmers were provided with individual soil health reports and fertilizer recommendations (rate, amount, and type). This program not only allows scientists and farmers to work closely and share information but also serves as a model for the nation to successfully transfer technology for improving soil health and sustainability

Genetic Markers of IgG Influence The Outcome of Infection with Hepatitis C Virus

We examined the role that immunoglobulin GM and KM allotypes—genetic markers of γ and κ chains, respectively—play in the outcome of hepatitis C virus (HCV) infection in white Americans. A total of 119 persons who had cleared HCV and 111 with persistent HCV infection were genotyped for the presence of several GM and KM determinants. Persistent HCV infection was more than three times as likely (odds ratio, 3.50; P = .01) in subjects who were carriers of the GM3 allele than in those who were noncarriers. These results show that particular GM alleles may be important determinants of the outcome of HCV infection

GM Allotypes and COVID-19. A Pilot Study Performed on Sicilian Patients

Several studies suggest that genetic variants that influence the onset, maintenance and resolution of the immune response might be fundamental in predicting the evolution of COVID-19. In the present paper, we analysed the distribution of GM allotypes (the genetic markers of immunoglobulin γ chains) in symptomatic and asymptomatic COVID-19 patients and in healthy controls, all born and residing in Sicily. Indeed, the role played by GM allotypes in immune responses and infection control is well known. Our findings show that the GM23 allotype is significantly reduced in healthy controls. Interestingly, in a previous study, Sicilians carrying the GM23 allotype were associated with the risk of developing a symptomatic Human Cytomegalovirus infection. However, a note of caution should be considered, due to the small sample size of patients and controls