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Lacking protein functions of Breast cancer susceptibility gene1 (BRCA1) and Breast cancer susceptibility gene2 (BRCA2), by methylation, represents tissue-specific silent epigenetic regions that tolerate genomic instability and may end in different cancers, mainly breast and ovary. Promoter-CpG island hypermethylation is a common molecular defect in cancer cells. This has prompted us to use MSP for identification of BRCA1 methylation in these groups of women at Duhok, north of Iraq. Genomic DNA was isolated from 96 tumor samples from patients with primary breast cancer and normal tissues which include; 40 non-neoplastic breast tissues (considered as external control) and 40 distant non-cancerous tissues from the same cancerous women (internal control). The extracted DNA was subjected to methylation-specific PCR (MSP) to determine the promoter methylation status of BRCA1 and its correlation with study parameters including protein expression level of ER, PR, Her2/neu, and Ki67 receptors. The study revealed 10.4% complete BRCA1 methylation and 66.6% partial methylation (PM) among the cancerous samples. Partial methylation was observed in 95% of internal control and 20% of the external control. Complete methylation was negative in both control groups. Compared with negative methylation, positive BRCA1 promoter methylation was significantly high among triple negative (ER-, PR-, Her2-) cases with high proliferative index. There was also a methylation trend toward cases with T2 and higher staging status, although didn't reach the level of significance. BRCA1 promoter complete methylation was exclusive for cancerous tissues. With management of the above concerns, this line of research gains a strength point including the prevalence of DNA methylation changes among sporadic breast cancer (i.e. not restricted to the inherited type). Considering partial or focal BRCA1 methylation, caution has to be taken as this epigenetic alteration, which may progress to complete methylation status, was detected in non-neoplastic breast tissues adjacent to the cancerous ones and even normal breasts. This triggers application of extended screening programs, including BRCA1 methylation, for identification of women at risk, and can benefit from early intervention.

Objective: To test the effect of some trace elements, on protein and lipoprotein glycosylation and their impact on the severity of diabetic retinopathy., Methods: A case control study was conducted in 42 diabetic patients (14 without retinopathy [DC]; 14 with non-proliferative diabetic retinopathy [NPDR]; 14 with proliferative diabetic retinopathy [PDR]) at Ebin Al-Haitham Specialized Hospital, Baghdad, Iraq for Ocular Diseases from February to December 2008. In addition to 20 age and gender matched healthy controls (NC). The glycation of albumin, alpha-, pre beta-, and beta-lipoproteins was measured by agarose gel electrophoresis. Serum levels of cadmium (Cd), selenium (Se), chromium (Cr), zinc (Zn), and copper (Cu) were analyzed by flameless atomic absorption spectrophotometer., Results: There was significant elevation in the mean serum glycated beta-lipoprotein in DC (p<0.05) and a near significant increase (p=0.06) in the means of both glycated albumin and pre beta-lipoproteins among the PDR and NPDR groups. Moreover, a significant reductions in serum means of Cd (p<0.05) and Zn/Cu ratios (p<0.001) were recorded in all diabetic retinopaths as compared to DC. The Cd level rises with the increase in duration of diabetes (p<0.001) and hyperglycemia (p<0.025) whereas, the serum Cr values decreases with the progression of diabetes (p<0.025)., Conclusion: Both glycation and oxidative processes are involved in the development of diabetic retinopathy, and changes in the concentration of Cd, Se, Cr, Zn, and Cu have some impact on the disease progression.