DNase2β Gene Variants May Explain Life in Chickens

Nicole Burdick, Kaitlyn Prentiss, and Efe Agbe-Rankhe

Abstract: Chickens (Gallus gallus) escape death by potential genetic mutation of DNase2β! Cells in the body are continuously dying and regenerating and deoxyribonuclease2(DNase2) plays an important role in this process. DNase2 are enzymes found in lysosomes that break down the DNA of dead cells during engulfment by phagocytes. There are multiple forms of these enzymes, including DNase2β and DNase2α. DNase2β is expressed in the eye to degrade nuclear DNA during lens cell differentiation. DNase2α degrades DNA of engulfed apoptotic cells. Previous studies have shown that loss of DNase2α gene in mammals caused death in utero, and they were unable to sustain life. Chickens only have DNase2β leading us to wonder how they survive without DNase2α. It is thought that two recently discovered variants X1 and X2 could be compensating for DNase2α-like expression. To isolate and determine if X1 and/or X2 are found in chicken tissue a reverse transcriptase reaction was performed on chicken liver and kidney tissue RNAs. Using the specific X1 and X2 primes, we are performing PCR to find and amplify X1 and X2 cDNAs. To visualize the PCR products, we are performing gel electrophoresis. This allows us to determine whether or not X1 and X2 are present in chicken tissues.