Search

Introduction: Genetic variants that control dopamine have been associated with obesity in children through loss of control of satiety and impulses, the manifestation of addictive eating behaviors, and specific personality traits. The variants include FTO -rs9939609 and the MAO-A 30 pb u-VNTR low-transcription alleles (LTA)., Objective: To evaluate the genetic association of FTO -rs9939609 and the MAO-A LTA, along with personality traits and eating behavior with obesity in Mayan children from Mexico., Methods: We cross-sectionally evaluated 186 children (70 with obesity and 116 with normal weight) 6-12 years old from Yucatan, Mexico. Nutritional status was defined with body mass index (BMI) percentiles. Personality traits were evaluated with the Conners and TMCQ tests; eating behavior was evaluated with the CEBQ test. Genotyping with real-time PCR and TaqMan probes was used for FTO -rs9939609, whereas PCR amplification was used for MAO-A u-VNTR., Results: High-intensity pleasure ( p = 0.013) and moderate appetite ( p = 0.032) differed according to nutritional status. Heterozygous FTO -rs9939609 T/A children showed higher mean scores of low-intensity pleasure ( p = 0.002) and moderate appetite ( p = 0.027) than homozygous T/T. Hemizygous boys having MAO-A LTA showed significantly higher mean scores of anxiety ( p = 0.001) and impulsivity ( p = 0.008). In multivariate models, only LTA alleles of MAO-A explained obesity in boys (OR = 4.44; 95% CI = 1.18-16.63)., Conclusion: In the present study, MAO-A u-VNTR alleles were associated with obesity in multivariate models only in boys. These alleles might also have a role in personality traits such as anxiety and impulsivity, which secondly contribute to developing obesity in Mayan boys., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Vázquez-Pérez, Hattori-Hara, Arankowsky-Sandoval, Pérez-Mendoza, Rubi-Castellanos, Rangel-Méndez, Pinto-Escalante, Canto-Cetina and González-Herrera.)

Zika virus was recognized as a teratogen in 2015, when prenatal Zika infection was associated with neonatal microcephaly. The transmission, virulence, tropism, and consequences of Zika virus infection during pregnancy are currently studied. Decreased neural progenitor cells, arrest in neuronal migration and/or disruption of the maturation process of the fetus central nervous system have been associated. Congenital Zika Syndrome produces a fetal brain disruption sequence resulting in structural brain abnormalities, microcephaly, intracranial calcifications, fetal akinesia and arthrogryposis. Vascular abnormalities like unique umbilical artery and decreased cerebral vascular flow have been described in some patients. This article reports a Zika positive patient with sequence of fetal brain disruption, arthrogryposis and absence of distal third of the right forearm. This report expands the clinical observations of congenital Zika syndrome that may be related to disruptive vascular events., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Contreras-Capetillo, Palma-Baquedano, Valadéz-González, Manrique-Saide, Barrera-Pérez, Pinto-Escalante and Pavía-Ruz.)

Mexican Maya populations have a notably high prevalence of type 2 diabetes (T2D) as a consequence of the interaction between environmental factors and a genetic component. To assess the impact of 24 single nucleotide variants (SNVs) located in 18 T2D risk genes, we conducted a family-based association evaluation in samples from Maya communities with a high incidence of the disease. A total of four hundred individuals were recruited from three Maya communities with a high T2D incidence. Family pedigrees (100) and 49 nuclear families were included. Genotyping was performed by allelic discrimination with TaqMan probes. This study also included the family-based association test (FBAT) statistic U to assess the genetic associations with T2D, and the multivariate statistical and haplotype analyses. A positive association with TD2 risk was found for WFS1 rs6446482 (p = 0.046, Z = 1.994) under an additive model, and SIRT1 rs7896005 (p = 0.038, Z = 2.073) under the dominant model. Multivariate model analysis, including T2D status, age, and body mass index (BMI), displayed significant covariance in PPARGC-1α rs8192678; SIRT1 rs7896005; TCF7L2 rs7903146 and rs122243326; UCP3 rs3781907; and HHEX rs1111875 with a P < 0.05. This study revealed an association of SIRT1 and WFS1 with T2D risk., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Objectives: Genetic variation of the fat mass and obesity associated gene (FTO) has been identified as a risk factor for obesity and obesity traits. Distribution of FTO single nutleotide polymorphisms (SNPs) rs1421085T>C, rs9939609T>A, rs8057044G>A and copy number variation (CNV) was evaluated in association with childhood obesity or overweight status in children with Mayan ethnicity., Methods: We included 318 school-aged children with obesity or overweight status (body mass index [BMI]: >85th percentile) and 303 children with normal weight (BMI: 15th-85th percentile). Genotyping was performed using real-time polymerase chain reaction (RT-PCR) with TaqMan probes. The cross-sectional study was carried out using univariate and multivariate logistic regression models adjusted for gender., Results: FTO-SNP rs1421085 showed significant differences between children with obesity and children with normal weight for the heterozygous genotype (P = 0.003) and for allele frequencies (P = 0.023). Adjusting by gender, significant differences were found in frequencies of the hetezygous genotype of SNPs rs9939609 (P = 0.023) and rs1421085 (P = 0.003) as well as in allele frequencies (P = 0.042 and P = 0.013, respectively) between girls with obesity and girls without obesity. In contrast, SNP rs8057044 was significantly different only between heterozygous overweight versus normal weight boys (P = 0.035) and for the allele frequency of rs8057044 (P = 0.021). The mean relative CNV was significantly higher in male overweight children than in boys with normal weight (P = 0.000)., Conclusions: The FTO SNP rs1421085 is a genetic factor associated with obesity in Mayan school-aged children. FTO SNPs rs1421085 and rs9939609 affect genetic susceptibility for obesity only in girls, whereas, SNP rs8057044 and CNV are associated with overweight status only in boys., (© 2018 Wiley Periodicals, Inc.)

Part of the work agenda of international health authorities is to define the clinical spectrum of the congenital Zika syndrome (CZS) in different territories. We describe the clinical variability that gave rise to the suspicion of CZS in 3 newborn patients in the south of Mexico with active transmission of Zika. All of them presented Zika RNA by reverse transcription-polymerase chain reaction and positive antibodies for IgM by enzyme-linked immunosorbent assay. None of the mothers tested positive for active viremia, only one mother had Zika-symptoms and titers of Zika-positive IgM. Intrauterine growth restriction, brain disruption sequence, and intracranial calcifications are the clinical characteristics common in all. One patient had neural tube defect and other, arthrogryposis. Because the majority of pregnant women will be asymptomatic to Zika, we must be alert to the clinical variability of the birth defects associated to pregnancy Zika infection. Reports of clinical cases encourage the medical community to make diagnostic decisions.

Background and Aims: It has been demonstrated that heterozygote and homozygote thiopurine S-methyltransferase (TPMT) mutant allele carriers are at high risk to develop severe and potentially fatal hematopoietic toxicity after treatment with standard doses of 6-mercaptopurine (6-MP) and methotrexate (MX). Those drugs are the backbone of acute lymphoblastic leukemia (ALL) and several autoimmune disease treatments. We undertook this study to determine the frequency of the TPMT deficient alleles in children with ALL and non-ALL subjects from Mexico City and Yucatan, Mexico., Methods: We included 849 unrelated subjects, of which 368 ALL children and 342 non-ALL subjects were from Mexico City, and 60 ALL cases and 79 non-ALL individuals were from Yucatan. Genotyping of the rs1800462, rs1800460 and rs1142345 SNPs was performed by 5'exonuclease technique using TaqMan probes (Life Technologies Foster City, CA)., Results: The mutant TPMT alleles were present in 4.8% (81/1698 chromosomes) and only 0.2% were homozygote TPMT*3A/TPMT*3A. We did not find statistically significant differences in the distribution of the mutant alleles between patients from Mexico City and Yucatan in either ALL cases or non-ALL. Nonetheless, the TPMT*3C frequency in ALL patients was higher than non-ALL subjects (p = 0.03). To note, the null homozygous TPMT*3A/TPMT*3A genotype was found in 2.5% of the non-ALL subjects., Conclusions: TPMT mutant alleles did not exhibit differential distribution between both evaluated populations; however, TPMT*3C is overrepresented in ALL cases in comparison with non-ALL group. Assessing the TPMT mutant alleles could benefit the ALL children and those undergoing 6-MP and MX treatment., (Copyright © 2016 IMSS. Published by Elsevier Inc. All rights reserved.)

Focal dermal hypoplasia (FDH; Goltz-Gorlin syndrome) is an X-linked dominant disorder affecting mainly tissues of ectodermal and mesodermal origin. The phenotype is characterized by hypoplastic linear skin lesions, eye malformations, hair and teeth anomalies, and multiple limbs malformations. The disorder is caused by PORCN mutations. Here we describe a mother and daughter with FDH in whom a c.938T>G in PORCN was detected. Neither of the two had FDH, but otherwise the phenotype was classical. Focal skin hypoplasia is a hallmark of FDH but the present family indicates that FDH should also be considered in absence of this skin manifestation., (© 2013 Wiley Periodicals, Inc.)

Objectives: Some Single nucleotide polymorphisms (SNPs) of several candidate genes have been associated with low bone mineral density (BMD) and fracture risk. As the genetic variability of such SNPs in Hispanic and Native American populations is scarce, we analyzed the three SNPs that have been related with bone mass disorders (Sp1, A163G, and BsmI) located in the genes of Type I Collagen (COL1A1), Osteoprotegerin (OPG), and Vitamin D receptor (VDR) in Mexican Mestizos (people resulting from post-Columbian admixture) and five Amerindian populations., Methods: We genotyped these three SNPs by Polymerase chain reaction (PCR) and Restriction fragment length polymorphisms (RFLPs) in 523 individuals from five Mexican Amerindian groups (Nahua, Maya, Purépecha, Tarahumara, and Huichol) and 227 western Mestizos (Jalisco state)., Results: The modal allele was the same in all the six populations for Sp1-COL1A1 (S > 77%), A163G-OPG (A > 80%), and BsmI-VDR (b > 62%). Genotype distribution was in Hardy-Weinberg equilibrium in all SNPs/populations, excepting Sp1-COL1A1 in the Purépecha group and BsmI-VDR in Mestizo. In terms of the presumably Sp1-COL1A1 risk allele to low BMD (allele "s"), the Purépecha group showed the highest allele (23%) and homozygous (14.5%) frequencies. If the role of this allele as a genetic predisposing factor to low BMD were confirmed, this would mean increased susceptibility of Purépechas with regard to Europeans (14.5 vs. 6.8%)., Conclusions: This finding presumably could influence the genetic susceptibility to low BMD in Purépechas. For the SNPs, BsmI-VDR and A163G-OPG, relative homogeneity was observed among the Mexican populations analyzed here., (Copyright © 2012 Wiley Periodicals, Inc.)

Background: Spina bifida (SB) is a common congenital malformation in Southeast Mexico. Parents of children with SB reside in areas with frequent pesticide spraying or have agriculture activities, suggesting potential exposure to pesticides. Paraoxonase 1 (PON1) is the responsible enzyme for deactivation of organophosphates (OP) in the central nervous system. Polymorphisms of PON1 genes influence the catalytic activity and plasma protein level of the enzyme, therefore, genotypic characterization of PON1 gene represents a potential predictor for susceptibility to OP-related effects., Methods: The frequency of PON1 haplotypes and polymorphisms (-108CT, L55M, and Q192R) were determined in this study. A case-control study was performed to evaluate the risk for having offspring affected by SB in 152 cases and 160 control parents. Polymorphisms were determined by PCR amplification and restriction fragment length polymorphism and Real Time-PCR. Odds ratios and confidence interval 95% were estimated., Results: Genotype frequencies for the three PON1 polymorphisms were distributed according to Hardy-Weinberg expectations (p > 0.05) and were significantly different between cases and controls (p < 0.05). The heterozygous CT genotype of -108CT polymorphism, the RR genotype of Q192R polymorphism, both LM and MM genotypes of L55M polymorphism, and the haplotypes 221 and 222 (for -108CT, L55M, and Q192R) were associated with the risk for having a child affected by SB (p < 0.02). The heterozygous -108CT genotype was associated only maternally, whereas the heterozygous L55M genotype was relevant only in the fathers. The RR homozygous genotype was relevant both in mothers and fathers, suggesting the importance of this substrate-specific polymorphism., Conclusion: Results suggest that PON1 polymorphisms are relevant risk factors for having offspring affected with SB in this population from Southeast Mexico., (© 2010 Wiley-Liss, Inc.)

Introduction: Between 60 and 65% of the mutations that cause Duchenne's/Becker's muscular dystrophy (DMD/BMD) are deletions in the dystrophin gene. Identifying deletions confirms the diagnosis and allows carriers to be detected with precision, which is the main preventive resource. The frequency and distribution of deletions in the DMD gene is unknown in south-east Mexico., Aims: To identify deletions in the DMD gene and to detect carriers in families with DMD/BMD in south-east Mexico., Patients and Methods: The study involved 26 families that showed clinical signs of DMD/BMD: Deletions were determined in the DNA of 40 males by means of the multiple polymerase chain reaction (PCR) in 22 segments of the gene. Detection of carriers was applied to 33 female relatives using PCR-restriction fragment length polymorphism of the polymorphic markers Pert 87.8/Taq 1, pERT 87.15/Bam H1, and single PCR for VNTR MP1P by linkage analysis., Results: Deletions were identified in 67.5% of patients with DMD and they were located in the 5' end and in the central region, exons 44 to 52, of the gene. In the detection of carriers, 73.33% of the families were informative. The markers 87.8/Taq 1 and MPIP yielded the greatest information power, with 26.67 and 33.33%, respectively. Of a total of 33 females, 21 (63.64%) were carriers, one (3.03%) was a non-carrier and 11 (33.33%) were not informative., Conclusions: The frequency of deletions was 67.5%. Carrier status was determined in 66.67% of the females who were analysed. The markers pERT 87.8/Taq 1 and MP1P yielded the greatest information power.

Background: Methylenetetrahydrofolate reductase (MTHFR) of the folate metabolism pathway is a candidate gene for neural tube defects (NTDs). Frequency of the second common polymorphism, A1298C, in the MTHFR gene is not well known in Mexico. Conflicting results exist regarding the association of A1298C-MTHFR with NTDs. One explanation for this controversy might be that alleles are differently distributed among various populations. The aim of the study was to determine the frequency of the A1298C-MTHFR polymorphism and its association with NTDs in a population of Yucatan, Mexico., Methods: Genotyping was performed by use of polymerase chain reaction with restriction fragment length polymorphisms using MbOII endonuclease (PCR-RFLPs MbOII). Allele and genotype frequencies were compared between cases with NTDs, their mothers and fathers with matched controls based on an association analysis using EpiInfo software., Results: A1298C genotypes were distributed according to Hardy-Weinberg expectations for all studied groups. Frequencies of allele C and heterozygous AC genotype were significantly higher in males (p = .006 and p = .011, respectively) in control group. Significant differences were not observed between cases and controls, except in mothers of NTD cases compared with mothers of healthy offspring for both allele C and heterozygous AC genotype (p = .009 and p = .01, respectively)., Conclusions: The polymorphism A1298C-MTHFR is not associated with NTDs, except for mothers, suggesting only a maternal association with having NTD-affected offspring in the Yucatan population. The frequency of allele C in the control population was 10%, which is significantly lower than in other reported control populations worldwide (p < .01)., (2007 Wiley-Liss, Inc.)

Introduction: Consanguineous unions occur in all populations around the world. Couples related as second cousins or closer have been observed with deleterious effect. Among the clinical effects of parental consanguinity, the incidence of offspring with congenital malformations (CM) increases approximately two-fold., Materials and Methods: A hospital database of neonates with CM was searched to select neonates with parental consanguinity and two control groups. One control group consisted of healthy neonates and the other control group consisted of neonates with CM but without parental consanguinity. Both control groups consisted of the first neonate of the same sex to be born after a consanguineous neonate with CM. Family, sociodemographic and anthropometric variables, as well as the severity of the malformations, were compared between the two groups with CM. Neonates with CM were grouped into five categories: Major multiple CM, minor multiple CM, isolated major CM, isolated minor CM, and specific diseases. The indigenous Mayan subpopulation was also analyzed., Results: Among 1117 neonates with CM, parental consanguinity was found in 21. Parental consanguinity was also found in 8 neonates in the group of healthy controls (OR 2.4 [1.05-5.95]). The most common form of consanguinity was between second cousins and was more frequent in the Mayan subpopulation. Major multiple CM were more frequent among consanguineous than among nonconsanguineous couples. No association was found between the severity of CM and the degree of relationship., Conclusions: The prevalence of consanguinity found in neonates with CM and healthy controls (1.9 % and 0.8 %) was similar to that found in other Latin populations. A higher prevalence was found in the Mayan population. Mayor multiple CM were more frequent among the neonates of consanguineous than among nonconsanguineous couples.

We describe an abnormal premature male infant with mosaic monosomy of chromosome 22. He had a unique facial appearance, similar to those with DiGeorge syndrome, and hypertonicity, limitation of extension at major joints, and flexion contractures of all fingers. This rare chromosomal aberration has been reported previously in 6 cases, three of them being nonmosaic and three mosaic patients. There was a great variability of expression among the anomalies of these patients. However, the most common anomalies were in the face and joints. A correlation between the severity of expression and percent of monosomic cells was not clear.

The Schwartz-Jampel syndrome is a rare disorder inherited as an autosomal recessive trait. The main clinical features of this syndrome include generalized myotonic myopathy, skeletal dysplasia, blepharophimosis, microstomia, contracture of joints and short stature. This report concerns a pair of female monozygotic twins with Schwartz-Jampel syndrome. Minor physical differences were found in the toes and joints affected. Additionally, both showed severe microcephaly and previously undescribed X-ray manifestations: a small skull, disproportion between skull and facial structures and dysharmonic bone maturation. This is the first report of identical twins with this syndrome.

The most common complication of pregnancy is fetal wastage in any of its manifestations. One of the causes of these reproductive losses is the presence of parental chromosomal aberration. The diagnosis of this cause permits appropriate specific risk for the couple reproduction. In this study, cytogenic analysis were performed to a group of couples with fetal wastage of unknown, to know whether some parental chromosomic aberrations were the etiologic cause of them. Were included 173 couples with two or more reproductive failures. In all couples, metaphase chromosome analysis of peripheral blood was performed, with trypsin-Giemsa banding and C standing. In five women (2.9%) it was found some chromosomal aberration. In all the men and in 168 women the karyotype was normal. In 2.8% of all the subjects it was found some polimorphic chromosome. Routinary chromosomal survey realized to couples with pregnancy looses of unknown cause is important to identify individuals carrying some chromosomal aberration.

Most cases of KTW syndrome are sporadic. However, in a few, other family members have some clinical manifestations of the syndrome, and an autosomal dominant mode of inheritance has been suggested. In this paper we present a family with an affected child who has large skin hemangiomata, overgrowth of the right leg, and severe heart defects. Her mother has a large capillary hemangioma on the left side of back and has developed severe varicosities in both lower extremities. The maternal grandmother developed severe varicosities in her legs at a young age. The clinical signs found in the mother and maternal grandmother represent a milder phenotype and might be explained as variable expressivity of the syndrome. The family tree supports autosomal dominant inheritance.

The chromosomes of 14 patients (9 males, 5 females) suffering from paroxysmal nocturnal hemoglobinuria in Merida, Mexico between April 1989 and July 1992 were analyzed. Four of the patients were children (range, 3-15 years old) and 9 were adults (range, 19-62 years old). None of the patients had any evidence of leukemic transformation and 9 of them had antecedent insecticide exposure. In 50%, the clinical presentation was anemia plus hemorrhagic syndrome. Only 1 case had thrombosis. The lapse between the beginning of the disease and the karyotypic analysis was 14.5 months on average (range, 1-172 months). In all cases we found a normal chromosomic complement. In addition, 5 patients had an acentric fragment in only 1 metaphase and one of these had a mar and Cq chromatid break in another metaphase, but neither could be considered as specific chromosomal abnormality for paroxysmal nocturnal hemoglobinuria.

We report on a 3-month-old girl with a TAR-like syndrome. Her older brother died with a similar disorder at 3 months of unknown causes. The parents are second cousins of Mayan ancestry. The infant also had, in addition to the usual abnormalities of TAR syndrome, depressed nasal bridge, cataracts, glaucoma, megalocorneae, and blue sclerae.