Abstract Background: Vitiligo is characterized by an autoimmune response targeting melanocytes, thus resulting in skin depigmentation. There are several genetic components involved in the development of vitiligo, of which various gene polymorphisms are currently considered as risk factors. For example, the CTLA4 (T-lymphocyte antigen 4) +49A/G (rs231775) and CT60 (rs3087243) gene variants have been associated with a predisposition for autoimmune diseases in different populations; however, their involvement in the development of vitiligo remains controversial. Objective: We evaluated the association between vitiligo and the CTLA4 +49A/G (rs231775) and CT60 (rs3087243) gene variants in a Mexican population. Methods: A total of 116 vitiligo patients and 117 control subjects from northeast Mexico were included in the study and analyzed through PCR-RFLP to determine whether there is an association between vitiligo and CTLA4 +49A/G (rs231775) and CT60 (rs3087243) gene variants. Results: No statistical difference was observed for both gene polymorphisms between vitiligo patients and controls (p > 0.05). Otherwise, vitiligo activity, family history of vitiligo, personal history of autoimmune diseases, or sex did not show any difference (p > 0.05). Conclusion: As suggested by the analysis of a northeastern Mexican population, the CTLA4 +49A/G (rs231775) and CT60 (rs3087243) gene variants do not constitute a risk factor in the development of vitiligo.

Resumen El objetivo del trabajo fue analizar los valores de hemoglobina glucosilada en el tercer trimestre de embarazo como predictores alternativos de la diabetes gestacional en pacientes del Noreste de México. Se trata de un estudio retrospectivo de casos y controles a partir de 121 expedientes de pacientes embarazadas, divididos en dos grupos, pacientes con diabetes gestacional (casos) y gestantes con valores glucémicos normales (controles). Se analizaron los factores de riesgo asociados a la diabetes gestacional y se obtuvo un punto de corte para la hemoglobina glucosilada. Se encontró que la obesidad materna, la edad y el antecedente del padecimiento fueron asociados significativamente con la diabetes gestacional. Valores de hemoglobina glucosilada ≥5% incrementaron el riesgo de padecer diabetes mellitus gestacional 4 veces y, aunado a un factor de riesgo, la probabilidad se incrementó 7 veces. Se concluye que los valores de hemoglobina glucosilada en el tercer trimestre de embarazo podrían emplearse como prueba diagnóstica de la diabetes gestacional en pacientes del Noreste de México. Sin embargo, aunque las diferencias encontradas fueron estadísticamente significativas, los resultados se deben interpretar con cautela y requieren su confirmación con estudios que incluyan una muestra mayor.

Abstract The objective of this study was to analise glycosylated hemoglobin values in the third trimester of pregnancy as an alternative predictor of gestational diabetes in North East Mexican cohort patients. This is a retrospective case-control study based on 121 records of pregnant patients, divided into two groups, patients with gestational diabetes (cases) and pregnant women with normal glycemic values (control). The risk factors associated with gestational diabetes were analised and a cut-off point for glycosylated hemogestaglobin was obtained. It was found that maternal obesity, age and a history of the condition were significantly associated with gestational diabetes. Values of glycosylated hemoglobin ≥5% increased the risk of suffering from gestational diabetes 4 times, and coupled with a risk factor, the risk increased 7 times. It is concluded that glycosylated hemoglobin values in the third trimester of pregnancy could be used as a diagnostic test for gestational diabetes in patients from the North East of Mexico. Although the differences found were statistically significant, our results must be interpreted with caution and require confirmation by studies with a larger sample.

Resumo O objetivo deste estudo foi analisar os valores da hemoglobina glicada no terceiro trimestre de gestação como preditores alternativos do diabetes gestacional em pacientes na região nordeste do México. Trata-se de um estudo retrospectivo de casos e controles utilizando 121 prontuários de gestantes divididas em dois grupos; pacientes com diabetes gestacional (casos) e gestantes com valores de glicemia normais (controles). Foram analisados os fatores de risco associados a diabetes gestacional obtendo-se um ponto de corte para a hemoglobina glicada. Descobriu-se que a obesidade materna, idade e antecedentes da doença foram associados significativamente ao diabetes gestacional. Valores da hemoglobina glicada ≥ 5% aumentaram o risco de padecer diabetes mellitus gestacional 4 vezes, e juntamente a um fator de risco, a probabilidade aumentou 7 vezes. Conclui-se que os valores da hemoglobina glicada no terceiro trimestre de gestação poderiam ser usados como teste diagnóstico do diabetes gestacional em pacientes da região nordeste do México. Embora as diferenças encontradas tenham sido estatisticamente significativas, os resultados devem ser interpretados com cautela e requerem confirmação através de estudos que incluam uma amostra maior.

Abstract Background: Alopecia areata is an autoimmune disease that produces non-scarring hair loss around the body. Gene variants of the cytotoxic T-lymphocyte antigen 4 (CTLA4) gene, a negative regulator of T-cell response, have been associated with a predisposition to autoimmune diseases in different populations; however, the involvement of these genetic variants in the development of AA is controversial. Objective: The present study evaluated the potential association of two CTLA4 gene variants with alopecia areata in a Mexican population. Methods: We genotyped +49AG (rs231775) and CT60 (rs3087243) variants in 50 AA patients and 100 healthy control participants through PCR-RFLP. Results: No statistical difference was observed for either of the gene variants regarding allele or genotype frequencies between AA patients and the controls when the parameters of family/personal history of autoimmune diseases or gender were considered (p > 0.05). Study limitations: Small sample size of patients and the data were obtained from Northeast Mexico population. Conclusion: The genetic variants rs231775 and rs3087243 of the CTLA4 gene are not a risk factor for the development of alopecia areata in the analyzed Mexican population.

Abstract: Background: Vitiligo is characterized by a lack of pigmentation in the skin. To date, there are no studies that analyze the changes in gene expression in the skin of vitiligo patients in response to narrow-band ultraviolet B (nb-UVB) phototherapy treatment. Objective: Explore the usefulness of new generation RNA sequencing in the identification of gene expression changes in the skin of vitiligo patients treated with nb-UVB phototherapy. Methods: Four skin biopsies (4mm in diameter) were collected from 45 Mexican vitiligo vulgaris patients, 2 specimens before and 2 after treatment with nb-UVB phototherapy, obtained from pigmented and non-pigmented tissue. RNA extracted from the biopsies was analyzed using the Illumina TruSeq Targeted RNA Expression protocol to study the expression of genes that participate in pathways of skin homeostasis. The 2 groups were compared using Student's t-test and the Mann-Whitney U-test. Results: The expression analysis identified differences in 12 genes included in this study after comparing the samples obtained before and after treatment: 5 genes involved in skin pigmentation, 2 genes involved in apoptosis, 2 genes involved in cell survival, 2 genes involved in oxidative stress responses and 1 gene involved in signal transduction mechanisms (p<0.05). Study limitations: The small size of skin biopsies limits the amount of RNA obtained, the number of genes to be analyzed and the use of conventional techniques such as RT-qPCR. Conclusion: We demonstrated usefulness of new generation RNA sequencing in the identification of gene expression changes, in addition to identifying new targets in the study of vitiligo.