The immunogenetic diversity of the HLA system in Mexico correlates with underlying population genetic structure.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) allele groups and alleles by PCR-SSP based typing in a total of 15,318 mixed ancestry Mexicans from all the states of the country divided into 78 sample sets, providing information regarding allelic and haplotypic frequencies and their linkage disequilibrium, as well as admixture estimates and genetic substructure. We identified the presence of 4268 unique HLA extended haplotypes across Mexico and find that the ten most frequent (HF > 1%) HLA haplotypes with significant linkage disequilibrium (Δ'≥0.1) in Mexico (accounting for 20% of the haplotypic diversity of the country) are of primarily Native American ancestry (A*02~B*39~DRB1*04~DQB1*03:02, A*02~B*35~DRB1*08~DQB1*04, A*68~B*39~DRB1*04~DQB1*03:02, A*02~B*35~DRB1*04~DQB1*03:02, A*24~B*39~DRB1*14~DQB1*03:01, A*24~B*35~DRB1*04~DQB1*03:02, A*24~B*39~DRB1*04~DQB1*03:02, A*02~B*40:02~DRB1*04~DQB1*03:02, A*68~B*35~DRB1*04~DQB1*03:02, A*02~B*15:01~DRB1*04~DQB1*03:02). Admixture estimates obtained by a maximum likelihood method using HLA-A/-B/-DRB1 as genetic estimators revealed that the main genetic components in Mexico as a whole are Native American (ranging from 37.8% in the northern part of the country to 81.5% in the southeastern region) and European (ranging from 11.5% in the southeast to 62.6% in northern Mexico). African admixture ranged from 0.0 to 12.7% not following any specific pattern. We were able to detect three major immunogenetic clusters correlating with genetic diversity and differential admixture within Mexico: North, Central and Southeast, which is in accordance with previous reports using genome-wide data. Our findings provide insights into the population immunogenetic substructure of the whole country and add to the knowledge of mixed ancestry Latin American population genetics, important for disease association studies, detection of demographic signatures on population variation and improved allocation of public health resources.

Genetic diversity of HLA system in three populations from Guanajuato, Mexico: Guanajuato City, León and rural Guanajuato.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 262 Mexicans from the state of Guanajuato living in the cities of Guanajuato (N = 78), León (N = 22) and rural communities (N = 162), to obtain information regarding allelic and haplotypic frequencies. We find that the most frequent haplotypes found in the state of Guanajuato include 12 Native American and three European haplotypes. Admixture estimates revealed that the main genetic components in the state of Guanajuato are Native American (50.64 ±â€¯2.11% by ML, 43.35% of Native American haplotypes) and European (44.14 ±â€¯1.14% by ML; 39.35% of European haplotypes), while African genetic component is less apparent (5.22 ±â€¯2.08% by ML; 8.36% of African haplotypes).

Genetic diversity of HLA system in two populations from Chiapas, Mexico: Tuxtla Gutiérrez and rural Chiapas.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 173 Mexicans from the state of Chiapas living in the city of Tuxtla Gutiérrez (N = 52) and rural communities (N = 121), to obtain information regarding allelic and haplotypic frequencies. We found that the most frequent haplotypes in Chiapas include 12 Native American and one European haplotype. Admixture estimates revealed that the main genetic components in Chiapas are Native American (71.61 ±â€¯0.58% by ML; 53.16% of Native American haplotypes) and European (26.39 ±â€¯5.05% by ML; 25.86% of European haplotypes), and a less prominent African genetic component (2.00 ±â€¯5.20% by ML; 9.77% of African haplotypes).

Genetic diversity of HLA system in two populations from Tamaulipas, Mexico: Ciudad Victoria and rural Tamaulipas.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 148 Mexicans from the state of Tamaulipas living in Ciudad Victoria (N = 23) and rural communities (N = 125), to obtain information regarding allelic and haplotypic frequencies. We found that the most frequent haplotypes in the state of Tamaulipas include ten Native American, three European and one African haplotypes. Admixture estimates revealed that the main genetic components in the state of Tamaulipas are Native American (54.69 ±â€¯0.93% by ML; 47.65% of Native American haplotypes) and European (34.66 ±â€¯5.62% by ML; 33.56% of European haplotypes), and a relatively high African genetic component (10.65 ±â€¯5.05% by ML; 12.42% of African haplotypes).

Genetic diversity of HLA system in two populations from Hidalgo, Mexico: Pachuca and rural Hidalgo.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 122 Mexicans from the state of Hidalgo living in the city of Pachuca (N = 41) and rural communities (N = 81), to obtain information regarding allelic and haplotypic frequencies. We find that the most frequent haplotypes in Hidalgo include eight Native American and one European haplotypes. Admixture estimates revealed that the main genetic components in Hidalgo are Native American (58.93 ±â€¯2.16% by ML; 54.51% of Native American haplotypes) and European (32.49 ±â€¯2.88% by ML; 28.69% of European haplotypes), and a relatively high African genetic component (8.58 ±â€¯0.93% by ML; 6.97% of African haplotypes).

Genetic diversity of HLA system in seven populations from Veracruz, Mexico: Veracruz city, Coatzacoalcos, Córdoba, Orizaba, Poza Rica, Xalapa and rural Veracruz.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 1113 Mexicans from the state of Veracruz living in the cities of Coatzacoalcos (N = 55), Orizaba (N = 60), Córdoba (N = 56), Poza Rica (N = 45), Veracruz (N = 171), Xalapa (N = 187) and rural communities (N = 539) to obtain information regarding allelic and haplotypic frequencies. We found that the most frequent haplotypes include 12 Native American haplotypes. Admixture estimates revealed that the main genetic components are Native American (64.93 ±â€¯1.27% by ML; 55.10% of Native American haplotypes) and European (26.56 ±â€¯0.89% by ML; 28.38% of European haplotypes), and a relatively high African genetic component (8.52 ±â€¯1.82% by ML; 8.78% of African haplotypes).

Genetic diversity of HLA system in two populations from Campeche, Mexico: Campeche city and rural Campeche.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 81 Mexicans from the state of Campeche living in the city of Campeche (N = 34) and rural communities (N = 47), to obtain information regarding allelic and haplotypic frequencies. We find that the most frequent haplotypes in the state of Campeche include ten Native American, three European, one African and one Asian haplotype. Admixture estimates revealed that the main genetic components in the state of Campeche are Native American (65.56 ±â€¯0.96% by ML; 51.24% of Native American haplotypes), European (34.44 ±â€¯10.94% by ML; 30.25% of European haplotypes), and a virtually absent African genetic component (0.00 ±â€¯10.31% by ML; 9.26% of African haplotypes).

Genetic diversity of HLA system in two populations from Oaxaca, Mexico: Oaxaca city and rural Oaxaca.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 636 Mexicans from the state of Oaxaca living in the city of Oaxaca (N = 151) and rural communities (N = 485), to obtain information regarding allelic and haplotypic frequencies. We found that the 13 most frequent haplotypes in Oaxaca are all of putative Native American origin. Admixture estimates revealed that the main genetic components in the state of Oaxaca are Native American (73.12 ±â€¯2.77% by ML; 61.52% of Native American haplotypes) and European (17.36 ±â€¯2.07% by ML; 20.69% of European haplotypes), and a relatively high African genetic component (9.52 ±â€¯0.88% by ML; 8.94% of African haplotypes).

Genetic diversity of HLA system in two populations from Puebla, Mexico: Puebla city and rural Puebla.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 2827 Mexicans from the state of Puebla living in the city of Puebla (N = 1994) and rural communities (N = 833), to obtain information regarding allelic and haplotypic frequencies. We found that the 16 most frequent haplotypes in Puebla are all of them Native American. Admixture estimates revealed that the main genetic components in the state of Puebla are Native American (72.21 ±â€¯1.25% by ML; 63.30% of Native American haplotypes) and European (21.05 ±â€¯1.92% by ML; 23.86% of European haplotypes), and a less prominent African genetic component (6.74 ±â€¯2.20% by ML; 6.20% of African haplotypes).

Genetic diversity of HLA system in two populations from Yucatán, Mexico: Mérida and rural Yucatán.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 324 Mexicans from the state of Yucatán living in the city of Mérida (N = 192) and rural communities (N = 132), to obtain information regarding allelic and haplotypic frequencies. We found that the most frequent haplotypes in the state of Yucatán include 16 Native American and one European haplotype. Admixture estimates revealed that the main genetic components in Yucatán are Native American (81.54 ±â€¯4.99% by ML; 62.92% of Native American haplotypes) and European (11.50 ±â€¯15.43% by ML; 23.26% of European haplotypes), and a less prominent African genetic component (6.96 ±â€¯10.47% by ML; 5.93% of African haplotypes).

Genetic diversity of HLA system in two populations from Morelos, Mexico: Cuernavaca and rural Morelos.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 112 Mexicans from the state of Morelos living in the city of Cuernavaca (N = 82) and rural communities (N = 30), to obtain information regarding allelic and haplotypic frequencies. The most frequent haplotypes in Morelos include seven Native American, one European, one African and one Asian haplotype. Admixture estimates revealed that the main genetic components in Morelos are Native American (60.43 ±â€¯2.22% by ML; 53.57% of Native American haplotypes) and European (39.58 ±â€¯3.70% by ML; 27.68% of European haplotypes), and a virtually absent African genetic component (0.00 ±â€¯4.93% by ML; but 11.16% of African haplotypes).

Genetic diversity of HLA system in two populations from Quintana Roo, Mexico: Cancún and rural Quintana Roo.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 98 Mexicans from the state of Quintana Roo living in the city of Cancún (N = 48) and rural communities (N = 50), to obtain information regarding allelic and haplotypic frequencies and their linkage disequilibrium. We found that the most frequent haplotypes in Quintana Roo include ten Native American and two European haplotypes. Admixture estimates revealed that the main genetic components in Quintana Roo are Native American (80.85 ±â€¯3.70% by ML; 60.20% of Native American haplotypes) and European (15.19 ±â€¯14.25% by ML; 26.02% of European haplotypes), and a less prominent African genetic component (3.96 ±â€¯10.75% by ML; 6.63% of African haplotypes).

Genetic diversity of HLA system in two populations from Tlaxcala, Mexico: Tlaxcala city and rural Tlaxcala.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 1011 Mexicans from the state of Tlaxcala residing in the city of Tlaxcala (N = 181) and rural communities (N = 830), to obtain information regarding allelic and haplotypic frequencies. We find that the ten most frequent haplotypes in Tlaxcala are all of Native American origin. Admixture estimates revealed that the main genetic components are Native American (75.13 ±â€¯1.56% by ML; 69.24% based on of Native American haplotypes) and European (16.10 ±â€¯4.98% by ML; 19.74% of European haplotypes), with a less prominent African genetic component (8.78 ±â€¯4.09% by ML; 4.35% of African haplotypes).

Genetic diversity of HLA system in two populations from Tabasco, Mexico: Villahermosa and rural Tabasco.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 224 Mexicans from the state of Tabasco living in the city of Villahermosa (N = 82) and rural communities (N = 142), to obtain information regarding allelic and haplotypic frequencies. We found that the most frequent haplotypes in Tabasco include 13 Native American and two European haplotypes. Admixture estimates revealed that the main genetic components in Tabasco are Native American (67.79 ±â€¯1.59% by ML; 56.25% of Native American haplotypes) and European (27.21 ±â€¯3.97% by ML; 29.91% of European haplotypes), and a less prominent African genetic component (5.01 ±â€¯4.42% by ML; 8.93% of African haplotypes).

Genetic diversity of HLA system in two populations from San Luis Potosí, Mexico: San Luis Potosí City and rural San Luis Potosí.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 117 Mexicans from the state of San Luis Potosí living in the city of San Luis Potosí (N = 30) and rural communities (N = 87), to obtain information regarding allelic and haplotypic frequencies. We find that the most frequent haplotypes in the state include 13 Native American, six European, two African and two Asian haplotypes. Admixture estimates revealed that the main genetic components are Native American (52.72 ±â€¯0.66% by ML; 48.29% of Native American haplotypes) and European (34.62 ±â€¯4.28% by ML; 32.48% of European haplotypes), and a relatively high African genetic component (12.66 ±â€¯4.61% by ML; 10.26% of African haplotypes).

Genetic diversity of HLA system in three populations from Coahuila, Mexico: Torreón, Saltillo and rural Coahuila.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 684 Mexicans from the state of Coahuila living in Saltillo (N = 72), Torreón (N = 396) and rural communities (N = 216), to obtain information regarding allelic and haplotypic frequencies. We find that the ten most frequent haplotypes found in the state of Coahuila include eight Native American and two European haplotypes. Admixture estimates revealed that the main genetic components in the state of Coahuila are European (49.72 ±â€¯4.18% by ML; 37.49% of European haplotypes) and Native American (45.01 ±â€¯2.69% by ML; 42.98% of Native American haplotypes), while African genetic component is less apparent (5.27 ±â€¯1.88% by ML; 9.92% of African haplotypes).

Genetic diversity of HLA system in three populations from Chihuahua, Mexico: Chihuahua City, Ciudad Juárez and rural Chihuahua.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 461 Mexicans from the state of Chihuahua living in Chihuahua city (N = 119), Ciudad Juárez (N = 106) and rural communities (N = 236), to obtain information regarding allelic and haplotypic frequencies and their linkage disequilibrium. We find that the most frequent haplotypes found in the state of Chihuahua include seven Native American and three European haplotypes. Admixture estimates revealed that the main genetic components in Chihuahua are European (52.12 ±â€¯0.88% by ML; 41.53% of European haplotypes) and Native American (39.51 ±â€¯2.17% by ML; 37.45% of Native American haplotypes), while African genetic component was less apparent (8.36 ±â€¯1.47% by ML; 11.70% of African haplotypes).

Genetic diversity of HLA system in a population from Guerrero, Mexico.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 144 Mexicans from the state of Guerrero to obtain information regarding allelic and haplotypic frequencies. We find that the ten most frequent haplotypes in the state of Guerrero include eight Native American and two European haplotypes. Admixture estimates revealed that the main genetic components in the state of Guerrero are Native American (61.36 ±â€¯2.69% by ML; 54.17% of Native American haplotypes) and European (35.01 ±â€¯4.59% by ML; 32.29% of European haplotypes), and a relatively low African genetic component (3.63 ±â€¯2.38% by ML; 5.90% of African haplotypes).

Genetic diversity of HLA system in a population sample from Aguascalientes, Mexico.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 95 Mexicans from the state of Aguascalientes to obtain information regarding allelic and haplotypic frequencies and their linkage disequilibrium. We find that the most frequent haplotypes in the state of Aguascalientes include four Native American, three European and one Asian haplotypes. Admixture estimates revealed that the main genetic components in the state of Aguascalientes are Native American (54.53 ±â€¯3.22% by ML; 44.21% of Native American haplotypes) and European (44.34 ±â€¯0.45% by ML; 40.53% of European haplotypes), and a relatively low African genetic component (1.13 ±â€¯2.33% by ML; 5.26% of African haplotypes).

Genetic diversity of HLA system in two populations from Michoacán, Mexico: Morelia and rural Michoacán.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 498 Mexicans from the state of Michoacán living in the city of Morelia (N = 150) and rural communities (N = 348), to obtain information regarding allelic and haplotypic frequencies. We find that the ten most frequent haplotypes found in the state of Michoacán include 12 Native American and two European haplotypes. Admixture estimates revealed that the main genetic components in the state of Michoacán are Native American (48.79 ±â€¯1.44%) and European (43.10 ±â€¯0.86%), while African genetic component is less apparent (8.11 ±â€¯0.85%). Our findings add to the growing knowledge on the population genetics of Western Mexico and provide new HLA data on populations from Michoacán.