5: Dynamic Genomes

what are the four modes of generating genetic diversity that can change a genome?

intragenic mutation, gene duplication/deletion, segment shuffling, horizontal gene transfer

what is the process of breaking and rejoining two homologous DNA double helices to create two DNA molecules with reciprocal exchanges of DNA known as?

homologous recombination

what is a type of homologous recombination that can cause gene amplification and deletion by leading to unequal crossovers?

illegitimate HR

what is a DNA sequence with a broken end that invades and anneals to the complementary strand of a homologous chromosome known as?

strand exchange

what is a type of transposable element that can enhance unequal crossovers called?

repetitive transposable elements

what are the three retrotransposons found in the human genome?

LINEs, SINEs, and Alu sequences

what is a type of mobile DNA element that moves via an RNA intermediate?

retrotransposon

what is the enzyme that synthesizes a double-stranded DNA copy from an RNA template, a gene product encoded by LINE-1 elements?

reverse transcriptase

which retrotransposon is approximately 6-8 kb in length, makes up about 21% of the human genome, and is still capable of transposition?

LINE-1 elements

which retrotransposons are smaller than LINEs, use reverse transcriptase from LINEs to move, and account for about 13% of the genome?

SINEs

which retrotransposons are about 300 nucleotides long, constitute 5% of the human genome, and are mostly no longer competent to transpose?

Alu sequences