Abstract Background: Ovarian cancer is the most lethal gynecologic cancer. Although most patients respond adequately to the first-line therapy, up to 85% experience a recurrence of disease, which carries a poor prognosis. Mitotic arrest deficiency 1 is a protein that helps in the assembly of the mitotic spindle assembly checkpoint by preventing anaphase until all chromatids are properly aligned. A single-nucleotide polymorphism in the MAD1L1 gene is prevalent in patients with advanced epithelial ovarian cancer and alters the way in which it responds to chemotherapy. Objective: The objective of the study was to study the relationship between the rs1801368 polymorphism of MAD1L1 and prognosis of ovarian adenocarcinoma. Methods: A total of 118 patients in whom the MAD1L1 gene was sequenced were analyzed using descriptive and comparative statistics. Results: Patients carrying the wild-type genotype had a higher distribution of early-stage disease. Having a MAD1L1 polymorphic allele increased the risk of being non-sensitive to chemotherapy. The median disease-free survival for patients with the wild-type MAD1L1 was 46.93 months, compared to 10.4 months for patients with at least one polymorphic allele. Conclusions: The rs1801368 polymorphism of MAD1L1 gene worsens prognosis in patients with ovarian adenocarcinoma. Traditional therapy for ovarian cancer might not be optimal in patients carrying this polymorphism.

Lung cancer is the leading cause of cancer mortality in Mexico and worldwide. In the past decade, there has been an increase in the number of lung cancer cases in young people, which suggests an important role for genetic background in the etiology of this disease. In this study, we genetically characterized 16 polymorphisms in 12 low penetrance genes (AhR, CYP1A1, CYP2E1, EPHX1, GSTM1, GSTT1, GSTPI, XRCC1, ERCC2, MGMT, CCND1 and TP53) in 382 healthy Mexican Mestizos as the first step in elucidating the genetic structure of this population and identifying high risk individuals. All of the genotypes analyzed were in Hardy-Weinberg equilibrium, but different degrees of linkage were observed for polymorphisms in the CYP1A1 and EPHX1 genes. The genetic variability of this population was distributed in six clusters that were defined based on their genetic characteristics. The use of a polygenic model to assess the additive effect of low penetrance risk alleles identified combinations of risk genotypes that could be useful in predicting a predisposition to lung cancer. Estimation of the level of genetic susceptibility showed that the individual calculated risk value (iCRV) ranged from 1 to 16, with a higher iCRV indicating a greater genetic susceptibility to lung cancer.