6.1 Chromosomal Mutations Part 4 Flashcards
What is the Hallmark symptom of Cri du chat syndrome?
enlarged glottis and larynx resulting in cat like cry
What is a duplication aberration?
when a portion of genetic material is repeated in any part of the genome
Why do duplications occur?
unequal recombination or replications errors occuring before meiosis
Do most of the offspring that have duplications survive?
yes
What is gene redundancy?
appearance of genes in multiple locations
What is an example of duplication that does not affect the individual?
duplications in rDNA
What is an example of a duplication that have an extensive alteration to phenotype?
Bar-eye phenotype in Drosophilia
What type of aberrations are instrumental in the process of evolution?
duplication
What are copy number variations?
individuals have different numbers of copies of sequences of DNA in both coding and noncoding regions of DNA
What plays a major role in the variation of individual traits?
CNVs
What have CNVs been associated with?
autism, type I diabetes, and certain cancers
What does having a high copy number of CCL3L1 do for an individual?
protective against HIV infection
What are individuals with high numbers of EPFG gene more responsive to?
treatment for non small cell lung cancer
What is the simplest type of translocation?
when two chromosomal arms come in close proximity and exchange genetic information
How many times would breaks have to happen for a translocation of internal information exchange?
four times (two on each chromosome)
What can translocation result in it does not have an equal exchange?
unbalanced; monosomy or trisomy
What are 95% of down syndrome cases a result of?
age-related accidental nondisjunction during meiosis in the mother
What is familial down syndrome at a genetic level?
parent is a carrier for a translocation that results in the majority of chromosome 21 being translocated to chromosome 14
What is a balanced carrier?
carrier for translocation but they are phenotypically normal
