IntroductionIn our genes, several different alleles determine whether or not a person will have a certain trait. The alleles constitute our genotypes and in this laboratory, we wanted to determine the genotypes of our class in the two loci: TAS2R38 and PV92. The TAS2R38 locus encodes a protein that involves the bitter taste of PTC; the gene determines whether or not a person will have a very bitter or no taste from PTC paper. People carrying the “T” allele are tasters while those who are homozygous recessive (tt) are non-tasters. The taster locus can be found on chromosome 7.3. The two different alleles present in the could be due to the effect of evolution and natural selection, as the same alleles can be found in chimpanzees.4 The PV92 locus does not encode any protein but rather involves an Alu. element with a length of 300 bp. A person with the “+” allele would have the element Alu making this sequence longer while those with the “-” allele would not have the element and would have a shorter sequence. This locus is located on chromosome 16.3. There are several Alu sequences among the primate genomes, but there are human-specific sequences, such as that found at the PV92.1 locus. In the experiment, the students' DNA was collected from cheek cells and PCR was used to target the loci and amplify the DNA region. In the taster gene, after amplification, restriction digestion was performed to differentiate the two alleles. The digest was able to show differentiation because those with the “T” allele would have two bands from the gel electrophoresis and those with “t” would have one band because the restriction enzyme does not cut it. For PV92, we were able to distinguish the alleles thanks to the additional length of the Alu element. Those...... middle of paper ......GE, Ioannou PA, Scheer WD, Herrera RJ et al. 1994. African origin of human-specific polymorphic Alu insertions. Evolution Vol. 91: pp 12288-122922 Gómez-Pérez L, Alfonso-Sánchez MA, Sánchez D, García-Obregón S, Espinosa I, Martínez-Jarreta B, De Pancorbo MM, Peña JA 2011. Alu polymorphisms in the Waorani tribe of the Ecuadorian Amazon Reflects the effects of isolation and genetic drift. American Journal of Human Biology Vol 23(6): pp 790-7953 Leicht BG, McAllister BF 2014. Foundations of Biology 1411, 2nd edition. Southlake, TX: Fountainhead Press. Pp 137, 163-168, 177-180.4 Wooding S. 2006. Phenylthiocarbamide: A 75-year adventure in genetics and natural selection. In: James F. Crow, William F. Dove Publishers. Perspectives, anecdotal and critical historical commentary on genetics. Salt Lake City, Utah: American Genetics Society. PP 2015-2023