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Noonan syndrome (NS) is inherited as an autosomal dominant disorder with dysmorphic facies, short stature, and cardiac defects, which can be caused by missense mutations in the protein tyrosine phosphatase nonreceptor type 11 (PTPN11) gene, which encodes src homology region 2 domain containing tyrosine phosphatase-2 (SHP-2), a protein tyrosine phosphatase that acts in signal transduction downstream to growth factors and cytokines. The current study aimed to study the molecular characterization of the PTPN11 gene among Egyptian patients with Noonan syndrome. Methods: Eleven exons of the PTPN11 gene were amplified and screened by single stranded conformational polymorphism (SSCP). DNA samples showing band shift in SSCP were subjected to sequencing. Results: Mutational analysis of the PTPN11 gene revealed T→C transition at position 854 in exon 8, predicting Phe285Ser substitution within PTP domain of SHP-2 protein, in one NS patient and –21C→T polymorphism in intron 7 in four other cases. Conclusion: Knowing that NS is phenotypically heterogeneous, molecular characterization of the PTPN11 gene should serve to establish NS diagnosis in patients with atypical features, although lack of a mutation does not exclude the possibility of NS.

MicroRNAs (miRNAs) are small non coding RNAs with essential roles, of which any alteration leads to several conditions. Their roles in diabetes (DM) and its vascular complications have not been completely assessed.to study the association of two miRNAs; 9 and 370, with biochemical parameters of type 2 diabetic (T2D), dyslipidemia and coronary artery disease (CAD).Blood samples were taken from 200 subjects of both genders, in the Outpatient clinic of Al Qasr El-Einy teaching hospitals, in which levels of both miRNAs (using real time PCR) and routine parameters were measured. Subjects were divided over four groups, 50 in each group as follows; patients with T2D, patients with CAD, patients with T2D and CAD, and healthy control subjects.miRNA 9 levels were expected to be over expressed in diabetic patients, while miRNA 370 levels were expected to be over expressed in those suffering from CAD and their association with CAD complication of T2D.miRNA 9 levels were significantly higher in T2D patients and T2D patients with CAD, (1.18±0.07, and 1.31±0.08 respectively), while miRNA 370 levels were significantly higher in T2D patients, CAD patients, and T2D patients with CAD (0.59±0.05, 1.00±0.05, and 1.20±0.06 respectively), compared to control group at p = 0.000. In addition both miRNAs were still significantly associated with each other even after conducting multiple regression analysis.This study associates the possible role of miRNAs in the diagnosis/prognosis of CAD complication of T2D.