Potential contribution of SIM2 and ETS2 functional polymorphisms in Down syndrome associated malignancies

Area of Science:

• Genetics
• Molecular Biology
• Oncology

Background:

• Transcription factors (TFs) regulate gene expression, crucial for development and disease.
• Down syndrome (DS) is associated with altered TF gene dosage and variable cancer incidence (higher leukemia, lower solid tumors).
• ETS2 and SIM2 are TFs involved in developmental and neurological pathways, with altered expression potentially impacting DS phenotypes.

Purpose of the Study:

• To investigate the association of functional genetic polymorphisms (fSNPs) in ETS2 and SIM2 genes with Down syndrome (DS) and cancer phenotypes.
• To understand how genetic variants in these TFs influence the risk and presentation of diseases in DS individuals.

Main Methods:

• In silico analysis to identify target pathways of ETS2 and SIM2.
• Identification and genotyping of fSNPs in ETS2 and SIM2 genes.
• Statistical association and interaction analyses in individuals with DS, their parents, and cancer patients (ALL, BC, OC) versus controls.

Main Results:

• Significant allelic/genotypic differences for fSNPs rs2070530, rs1051476, rs11254, and rs711 were observed in DS subjects compared to controls.
• rs711 showed distinct genotypic patterns in parents of DS individuals and breast cancer (BC) patients, with independent main effects.
• rs11254 demonstrated an independent main effect in DS subjects, while high entropy values for rs461155 were noted in solid tumor groups. Significant interactive effects were found for rs2070531 with other SNPs in most groups.

Conclusions:

• Altered frequencies and effects (independent/interactive) of fSNPs in ETS2 and SIM2 contribute to differential expression of these TFs in DS and malignant conditions.
• The variable expression of ETS2 and SIM2 due to genetic polymorphisms may underlie the differing incidences of various cancers observed in individuals with Down syndrome.