Noonan syndrome affects 1 in 1,000 to 2500 births yearly and results in short stature and congenital heart defects. Mutations in the developmental Ras/Raf/mitogen-activated protein kinase Ras/MAPK) pathway generate Noonan syndrome. Many studies have found case reports in which leucine zipper–like transcriptional regulator 1 (LZTR1) brings about Noonan syndrome. Although many scientists have examined Noonan syndrome in humans, not many of them have found the role in Drosophila (which is crucial as Drosophila is a model organism) Thus, this study examined the role LZTR1 in vein tissue, wing area, (The Ras/MAPK pathway directly influences the size of a fruit fly’s wing) and lifespan of the Drosophila to model the role of LZTR1 in the Ras/MAPK pathway. MAPK Kinase (MEK) (a known inhibitor of the pathway) was used as a positive control. It was found that although the lifespan did not make any difference for each LZTR1 mutated and MEK group compared to the Wild-Type (WT) groups (p > 0.05), Drosophila that carried mutations for LZTR1 and MEK had significantly more vein tissue (p < 0.001) and significantly smaller wings (p < 0.05), suggesting that LZTR1 affects the pathway. Future research may include using the information found in this study to test treatments on Drosophila to alleviate some of the symptoms in Noonan syndrome.

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