C 5c

GENERATION OF PSEUDOGENES

A) NONPROCESSED PSEUDOGENE

i) Unequal Crossing Over During Meiosis

regulating exon intron exon, ^_

ii) Unequal Sister Chromatid Exchange After Replication

B) PROCESSED PSEUDOGENE

m m loop causes misalignment x:

B) PROCESSED PSEUDOGENE

Transcription

CAP I

Reverse Transcription

TTTTn

Genomic Integration

Nicked Genomic DNA

Figure 1. Generation of pseudogenes. (A) Direct duplication of a DNA sequence including regulatory elements and introns yields a nonprocessed pseudogene. (B) Duplication via an RNA intermediate, processed with a 3' polyadenylated tail, 5' cap (7-methylguanosine), and intron removal, yields a retropseudogene. The arrows indicate direct repeat sequences resulting from the integration. The A-T refers to a stretch of adenines and complement thymines in the newly derived pseudogene.

chromatid a replicated chromosome before separation from its copy gene may be rendered nonfunctional. Genes and pseudogenes derived from the duplication of an ancestral gene are said to be paralogous.

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