Arylsulfatase A pseudodeficiency in Mexico: Enzymatic activity and haplotype analysis.

BACKGROUND: Metachromatic Leukodystrophy (MLD, OMIM 250100) is a neurodegenerative disease caused by mutations in the ARSA gene (OMIM 607574) that lead to deficiency in Arylsulfatase A (ASA). ASA pseudodeficiency (PD-ASA) is a biochemical condition that substantially diminishes ASA activity but is not associated with clinical manifestations. PD-ASA is associated with the c.1055A>G (p.Asn352Ser) (rs2071421) and c.*96A>G (rs6151429) variants, which have an estimated frequency of 2% in the population. OBJECTIVE: To determine the activity of Arylsulfatase A and to identify variants and haplotypes in the ARSA gene in Mexican individuals with pseudodeficiency. METHODS: Two-hundred apparently healthy individuals were included to determine the enzymatic activity of ASA in leukocytes by spectrophotometric analysis, and identification of the PD-ASA alleles was performed by PCR-RFLP assays. Genotypes were confirmed by semi-automated Sanger sequencing. Haplotypes were constructed using Arlequin v.10.04, and linkage disequilibrium analysis was performed with Cube X. RESULTS: The enzymatic activity of ASA was determined to be 1.74-2.09 nmol/mg protein/min and later correlated with genotypes and haplotypes. For the (p.Asn352Ser) variant, we found 126 (0.63) individuals with the AA genotype, 62 with AG (0.31) and 12 with GG (0.06); the frequency of the polymorphic allele was 0.215 (86 alleles, 21.5%), and the variant was in HWE (p = .2484). The variant c.*96A>G was also in HWE (p = .2105): 185 individuals (0.925) with the AA genotype, 14 (0.07) with AG, and 1 (0.005) with (GG), with a frequency of 0.04 (4%) for the polymorphic allele. The inference of haplotypes resulted in 312 (0.78) AA, 72 (0.18) GA, and 16 (0.04) GG haplotypes. The AG haplotype was not found. The variants were found to be in linkage disequilibrium (D' = 1). Of the nine possible diplotypes, AA/AG, AA/GG, and AG/GG were not found, in concordance with the hypothesis that the G allele of c.*96A>G does not occur in the absence of the G allele of c.1055A>G. We found a slight correlation between ASA biochemical activity and variants, mainly due to the G allele of c.*96A>G in either genotypes or haplotypes. CONCLUSIONS: In Northwestern Mexico, the presence of PD-ASA alleles was biochemically and molecularly determined, and the frequencies were found to be in HWE. The frequency of PD-ASA for the North Western Mexican mestizo is 8%.

Author Correction: Association between G1733A (rs6152) polymorphism in androgen receptor gene and recurrent spontaneous abortions in Mexican population.

The original version of this article unfortunately contained two mistakes in the Abstract and the Discussion sections that the authors would like to correct.

Association between G1733A (rs6152) polymorphism in androgen receptor gene and recurrent spontaneous abortions in Mexican population.

INTRODUCTION: Recurrent spontaneous abortion (RSA) is a multifactorial condition that occurs with a frequency of 0.2-5% in women of reproductive age. Among genetic factors, the single nucleotide polymorphism (SNP) G1733A in the androgen receptor (AR) gene has been associated with its presence in Greek and Iranian populations. Therefore, the aim of this study is to determine its possible association with RSA in this population. PATIENTS AND METHODS: A total of 156 Mexican RSA (with at least 2 consecutive abortions) unrelated patients and 152 unrelated healthy women were included, the presence of karyotype anomalies in the parents as well as uterine anomalies as well as antiphospholipid antibodies was excluded in patients; while all the controls presented at least two healthy pregnancies and no abortion. In all the included women, the presence of the SNP G1733A was determined by restriction fragment length polymorphism (RFLP) technique. RESULTS: No significant differences were observed in age between groups. The genotype GG, GA, and AA had a frequency of 0.70, 0.27, and 0.03 in patients and of 0.89, 0.10, and 0.01 in controls [corrected] (p < 0.001); while the A allele frequency was of 0.06 and 0.16 in controls and patients, respectively (p < 0.0001). The difference in allele frequency increased 10-15% when patients with primary RSA (with no live births) and with at least three abortions were included. CONCLUSIONS: The SNP G1733A of the AR gene is significantly associated with RSA in Mexican patients. These results coincide with previous reports in other populations.

[Human leukocyte antigen-G (HLA)-G as a biomarker in cancer]. / Antígeno leucocitario humano G (HLA-G) como biomarcador en cáncer.

Human leukocyte antigen is a class I HLA classic molecule that is preferentially expressed in cytotrophoblast cells and participates in tolerance and immune system suppression. The expression of HLA-G is induced in viral infections, autoimmune disorders, and cancers. Currently, HLA-G is considered a biomarker in the diagnosis, prognosis, and therapy of cancer.