Lecture 3 Flashcards
(15 cards)
There are about ___ billion base pairs per haploid set of DNA. However, there are only about ___ thousand protein encoding genes, which account for less than 50 million base pairs (about 2% of all DNA.)
3 billion
20 thousand
2 neighboring genes have extragenic DNA between them, which accounts for about ____ % of DNA.
75%
About 2/3 of human DNA is comprised of ______ sequences (both functional - Repeated genes, centromeres, and _____, and “non-functional” - less likely to be conserved.)
Repeated
Telomeres
Some examples of transcribed functional repeated DNA (about 1% of our genome) are ribosomal DNA, transfer RNA genes, and protein gene families like P___, globins, histones, etc.
P450
Transposable elements are examples of “non-functional” DNA. There are 2 kinds:
- Transposon - a segment of DNA is essentially cut out and moved into another portion of DNA
- Retrotransposon - encodes a ______ transcriptase and an _____ (incorporates the replicated DNA into new location.)
Reverse transcriptase
Integrase
____ sequences are the most abundant pseudogene in the human genome. They are classified as one form of ____ (short interspersed elements), and are the product of reverse transcription of the ____ recognition particle (SRP - RNA involved in moving specific proteins into and through cellular membranes.)
ALU
SINE
Signal recognition particle
About half of the human genome is derived from ______ elements.
Transposable
Transposons that “hop” into an _____ usually KO a gene’s function. If it hops into the end of a gene, it may have a lesser effect/phenotype.
Exon
If a transposon replicates and integrates into another chromosome, ______ recombination can now occur between chromosomes that are normally non-_______. This can lead to gene duplication and loss of other genes.
Homologous recombination
non-Homologous
Transposon location and composition is somewhat variable in _______ families.
Unrelated
SNPs are basically the same as a point mutation and occur at a __% frequency. SNP presence or absence can be used to trace linkage of a chromosome segment - genomic mapping.
1%
300 million SNPs have been identified and mapped. Bc of meiotic recombination, everyone has a different combination of SNPs that allows you to ______ that person.
Genotype
____ SNPs are those found outside of the gene region in DNA, and are so called because they can affect the regulation of other genes. _____ SNPs are those found within the regulatory or coding sequences of a gene. If found in the regulatory region, they can affect the _____ of the gene product produced, and if located in the coding region, they will change the ___ ___ sequence of the protein product (some change the functionality.)
Linked
Causitive
Amino acid
Restriction Fragment Length Polymorphism (RFLP) is an SNP in a _____ enzyme site, disrupting the ability of the enzyme to cut the DNA at that point, resulting in larger fragments. RFLPs can be caused by insertions (including transposons) or deletions.
Restriction enzyme
Simple Sequence Repeat polymorphisms (SSR) can lead to _______ rearrangements.
Unbalanced
