genetics test 2 ch 16(18) repeat expansions

Card Set Information

Author:
doncheto
ID:
288065
Filename:
genetics test 2 ch 16(18) repeat expansions
Updated:
2014-11-10 16:39:51
Tags:
genetics repeat expansions
Folders:

Description:
repeat
Show Answers:

Home > Flashcards > Print Preview

The flashcards below were created by user doncheto on FreezingBlue Flashcards. What would you like to do?


  1. TNRE
    _ _ _ expansion of 3-base repeat

    • Fragile X disease
    • - dominant, X linked
    •  CGG, changes in # of repeats in the untranslated region of
    •  FmR-1 gene (retardation) - product regulates translation of other protein, plays a role in development of synapses.
  2. BER
    • BER: Base Excision Repair
    •  repair oxidative damage, UV photo products uracils DNA

    step 1 enzyme N-glycosylase recognizes abnormal base, cleaves btwn base and sugar.

    step 2 Endonuclease recognizes gap (missing base), nicks backbone on 5' side

    step 3 5' to 3' exnuclease removes base

  3. NER
    • nucleotide excision repair
    • Fix many types mutation, thymine dimers, missing bases, chemically modified bases. 
    • * uses different enzymes than BER
    • * Removes more bases than BER
  4. NER process
    • 1. UVrA,B scan DNA, recognization of bultky lesions
    • - 20-50 copies in cells

    2. UVrB binds to damage site, cause uVrA to dissociate

    Recruits UVrC, binds to UVrB, makes dual cut in DNA.

    3. 

    4.
  5. Xerodema Pigmentosum (XP)
    • -autosomal recessive
    • -caused by mutations in NER proteins
    •                    -typically 8 or more genes
    • - features of disease result of a build up of unrepaired DNA (UV damage)
  6. mmR (E-coli)
    • mismatch Repair
    • * fixes mutations that polymerase should have found. (3' to 5' proofreading)

    • 1. Recognize mismatched base
    • *2. Determine which is the incorrect one

    3. Excise incorrect base, carry out repair synthesis.

    • Replication errors produce miss-match on newly synthesized DNA.
  7. bacteria methylation
    • methylate DNA @ Adenines in GATC sequences
    • * Directly after replication, the DNA is hemi-methylated, lag time before adenine methylase adds CH3

What would you like to do?

Home > Flashcards > Print Preview