Juan Pablo Meza-Espinoza

XRCC1 polymorphisms and haplotypes in Mexican patients with acute lymphoblastic leukemia

We examined the influence of the Arg194Trp, Arg280His, and Arg399Gln polymorphisms of XRCC1 (X-ray repair cross-complementing group 1) on the development of childhood acute lymphoblastic leukemia (ALL) in 120 ALL patients and 120 controls in Mexico. All of them were genotyped for these polymorphisms, using polymerase chain reaction. No significant differences in allele and genotype frequencies for any polymorphism were observed between patients and controls. Estimation of haplotypes showed the eight expected haplotypes (A-H), seven of which were found in both patients and controls; haplotype A (Arg-Arg-Arg) was the most common, whereas haplotypes F and G were absent in patients and controls, respectively. Haplotype B (Trp-Arg-Arg) was found to be associated with an increased risk of ALL (odds ratio (OR) = 1.95, 95% confidence interval (CI) = 1.13-3.37; P = 0.016), particularly in males (OR = 2.65, 95%CI = 1.25-5.63; P = 0.01). Individually, the 194Trp, 280His, and 399Gln alleles were not associated with significantly increased risk for ALL in these Mexican children.

Chromosomal Abnormalities in Couples with Reproductive Disorders

Aim: To determine the prevalence of chromosomal abnormalities in couples with reproductive disorders. Methods: A retrospective study was performed in 939 Mexican couples with reproductive disorders (542 with recurrent fetal loss, 356 with malformed/stillborn children, and 41 with sterility) whose karyotype was established on GTG-banded metaphases. Results: A chromosomal aberration was detected in one partner of 52 couples, including a double translocation carrier; therefore, the prevalence of chromosomally abnormal couples was 5.5%; 31 couples with recurrent fetal loss (31/542, 5.7%), 15 with malformed/stillborn children (15/356, 4.2%), and 6 with sterility (6/41, 14.6%). There were 43 couples with structural rearrangements (29 reciprocal translocations, 10 robertsonian translocations, 2 inversions, 1 insertion, and 1 ring) and 9 with gonosomal aneuploidies. The affected partner was female in 28 (53.8%) and male in 24 (46.2%) couples. In addition, 17 couples (1.8%) with the structural variant inversion 9qh were detected. Conclusion: The prevalence of chromosomal abnormalities found in our sample is consistent with figures described in several populations around the world.

MDR1 C3435T Polymorphism in Mexican Children with Acute Lymphoblastic Leukemia and in Healthy Individuals

Abstract To determine the influence of the MDR1 C3435T polymorphism on the development of childhood acute lymphoblastic leukemia (ALL), we studied 107 children with ALL and 111 healthy subjects. All subjects were genotyped for the C3435T polymorphism using the polymerase chain reaction–restriction fragment length polymorphism method. The genotype frequencies in the patients were 17% homozygous CC, 61% heterozygous CT, and 22% homozygous TT; in healthy individuals the genotype frequencies were 14% CC, 53% CT, and 33% TT. In patients with ALL the allele frequencies were 0.47 for the C allele and 0.53 for the T allele; in the healthy group these allele frequencies were 0.40 and 0.60 for the C and T alleles, respectively. No significant differences in allele frequency (p > 0.176) and genotype frequency (p > 0.255) were detected between the two groups. These findings suggest that the CT or TT genotype does not increase the risk for childhood ALL in Mexican patients. On the other hand, significant differences in allele frequencies were detected in the comparison of Mexican healthy subjects with other populations. Whether these differences are fortuitous or related to diverse genetic backgrounds remains to be elucidated.

Association of a serotonin transporter gene (SLC6A4) 5-HTTLPR polymorphism with body mass index categories but not type 2 diabetes mellitus in Mexicans

The serotonergic system has been hypothesized to contribute to the biological susceptibility to type 2 diabetes mellitus (T2DM) and body-mass index (BMI) categories. We investigate a possible association of 5-HTTLPR polymorphism (L and S alleles) in the promoter region of the serotonin transporter gene (SLC6A4) with the development of T2DM and/or higher BMI by analyzing a sample of 138 individuals diagnosed with T2DM and 172 unrelated controls from the Mexican general population. In the total sample genotypes were distributed according to Hardy-Weinberg equilibrium, and S allele frequency was 0.58. There was no statistical association between 5-HTTLPR polymorphism and the development of T2DM in this Mexican population sample (p = 0.12). Nevertheless, logistic regression analysis of the L allele and increased BMI disclosed an association, after adjusting for age, sex and T2DM (p = 0.02, OR 1.74, 95% CI: 1.079–2.808).

Promoter polymorphism of the serotonin transporter gene influences the number of sexual partners and smoking habits in a Mexican Mestizo population.

Medicine and Engineering in Computer Systems Faculty of Matamoros (FMeISC), Autonomous University of Tamaulipas (UAT), Human Genetics Institute, University Center for Health Science (CUCS), University of Guadalajara (UdeG), Clinic Department, Los Altos University Center (CUALTOS), University of Guadalajara (UdeG), Genetic Wing, West Center of Biomedical Research (CIBO), Mexican Social Security Institute (IMSS), Department of Molecular Biology and Genomics, University Center for Health Science (CUCS), University of Guadalajara (UdeG), Molecular Genetics Laboratory, Molecular Medicine Wing, West Center of Biomedical Research (CIBO), Mexican Social Security Institute (IMSS), Immunobiology Laboratory, University Center for Biological and Agricultural Sciences (CUCBA), University of Guadalajara (UdeG), Masters Academic Program in Forensic Sciences and Criminology , UAM Reynosa-Aztlán, Autonomous University of Tamaulipas (UAT), Mexico and Center for Biomedical Studies, University of Texas at Brownsville, USA

Genetic Epidemiology of Type 2 Diabetes in Mexican Mestizos.

There are currently about 415 million people with diabetes worldwide, a figure likely to increase to 642 million by 2040. In 2015, Mexico was the second Latin American country and sixth in the world in prevalence of this disorder with nearly 11.5 million of patients. Type 2 diabetes (T2D) is the main kind of diabetes and its etiology is complex with environmental and genetic factors involved. Indeed, polymorphisms in several genes have been associated with this disease worldwide. To estimate the genetic epidemiology of T2D in Mexican mestizos a systematic bibliographic search of published articles through PubMed, Scopus, Google Scholar, and Web of Science was conducted. Just case-control studies of candidate genes about T2D in Mexican mestizo inhabitants were included. Nineteen studies that met the inclusion criteria were found. In total, 68 polymorphisms of 41 genes were assessed; 26 of them were associated with T2D risk, which were located in ABCA1, ADRB3, CAPN10, CDC123/CAMK1D, CDKAL1, CDKN2A/2B, CRP, ELMO1, FTO, HHEX, IGF2BP2, IRS1, JAZF1, KCNQ1, LOC387761, LTA, NXPH1, SIRT1, SLC30A8, TCF7L2, and TNF-α genes. Overall, 21 of the 41 analyzed genes were associated with T2D in Mexican mestizos. Such a genetic heterogeneity compares with findings in other ethnic groups.

Contents Vol. 66, 2008

M.A. Belfort, Provo, Utah J. Bornstein, Nahariya H.L. Brown, Durham, N.C. C. Chapron, Paris P.G. Crosignani, Milan J. de Haan, Maastricht G.A. Dekker, Adelaide J.A. Deprest, Leuven K. Hecher, Hamburg S. Kahhale, São Paulo H. Kliman, New Haven, Conn. T.F. Kruger, Tygerberg J.A. Kuller, Raleigh, N.C. M.J. Kupferminc, Tel Aviv H. Minkoff , Brooklyn, N.Y. J. Moodley, Congella J.M. Mwenda, Nairobi H. Odendaal, Tygerberg J.T. Repke, Hershey, Pa. G.R. Saade, Galveston, Tex. Founded 1895 as ‘Monatsschrift für Geburtshilfe und Gynäkologie’, continued 1946–1969 as ‘Gynaecologia’ and 1970–1977 as ‘Gynecologic Investigation’