BPS 3101 Lecture Notes - Lecture 9: Tandemly Arrayed Genes, Alu Element, Tandem Repeat

• School: University of Ottawa
• Department: Biopharmaceutical sciences
• Course: BPS 3101
• Professor: Linda Bonen

Document Summary

Most genes are in non-repetitive dna regions: but low-to-mid repetitive dna fraction includes multi-gene families. 2. (i) dispersed (eg. actin genes on different chromosomes) 3. (ii) in tandem arrays (eg. rrna genes, globin genes: uneven gene density, absence of genes in centromeric regions, multigene families on different chromosomes. Variation in rdna (28s + 5. 8s + 18s) copy number among eukaryotes. Pseudogenes: defective, non-functional gene copies, how do pseudogenes arise, 1. Nonsense mutations or frame shift mutations (or point mutation within initiation codon: 2. Truncation part of gene missing because of deletion or rearrangement: 3. Tandem repetitive dna in eukaryotic genomes: chromosome architecture, centromere: in humans, 1500 30,000 copies of 171 bp tandem repeat (alphoid. Interspersed repetitive dna (typically non-genic, but can occur within introns: scattered around genomes, not in tandem repeats, (i) lines: long interspersed nuclear elements, non-ltr retro elements, encode rt, retro: rna to dna.