Crime Scene Investigation

1) Explain the content of the human genome: % protein encoding, % regulatory, % STRs AND distinguish locus from gene from alleles

-There is less than 2% protein encoding (code for proteins) in the human genome, around 3% STRs (short sequences of non-coding DNA), and around 8% regulatory genes that control gene expression

http://upload.wikimedia.org/wikipedia/commons/thumb/6/64/Components_of_the_Human_Genome.jpg/370px-Components_of_the_Human_Genome.jpg

 -A locus is the position of a gene on a chromosome

-A gene is the specific part of DNA base pairs on a chromosome that code for a phenotype

-An allele is a different type of gene in the same locus

http://www.csulb.edu/~kmacd/361-6-Ch1_files/allele.jpg

2) Explain the use of STRs in profiling to demonstrate the rarity of sharing all/most/many STRs

STRs (short tandem repeats) are used in DNA profiling because they can be highly polymorphic, which means there are many varieties of it. Therefore, STRs are very unique to each individual and therefore it can be used to discriminate between individuals esp. at a crime scene. 

3) State and describe the evidence of the gel to identify the suspect at the crime scene by referring the alleles found at the crime scene and the allele of the suspect(s)

-On the gel, the second column is the DNA found in the crime scene, which is subsequently followed by Suspect A in column three, Suspect B, Suspect C and Suspect D in the next three columns.

-As you can see below, the DNA found at the crime scene is exactly in line with Suspect C of the fourth column. This is because the alleles (one blue dash is an allele) exactly correspond