If a person is homozygous for the presence of an ALU repeat in the PV92 region, you would expect the size of the DNA fragment to be smaller compared to those with no ALU repeats. a. True  b. False

Unanswered As a hobby you propagate a population of worms. You notice that one worm is now clear instead of being tan. You trace down the mutation and discover that it is a single basepair deletion in a pigmentation gene. Explain how a single basepair deletion could result in a drastic mutant phenotype. Your answer Write your response here... ion on

You have the following DNA sequence: 5'GGT ACG TTG GGG CTC CAT3' This sequence is transcribed and translated. If the G that is underlined changes to to a C the result will be - A) A nonsenese mutation B) A frameshift mutation C) A silent substitution D) A missense mutation You have the following DNA sequence: 5'GGT ACG TTG GGG CTC CAT3' This sequence is transcribed and translated. If the G that is underlined is deleted, then the result will be A) A nonsense mutation B) A frameshift mutation C) A silent substitution D) A missense mutatio If there are 3000 bases in the coding region of a gene, the gene will have A) 3000 amino acids B) 6000 amino acids C) 1000 amino acids D) 3000 codons

Friedreich ataxia (FRDA) is an autosomal recessive, neurodegenerative disease that causes a lack of voluntary coordination of muscle movements.  Affected individuals are homozygous for an unusually large number (expansion) of repeats of a trinucleotide sequence (GAA) in the first intron of the X25 gene.  Unaffected individuals typically have between 7 and 38 repeats of the trinucleotide (GAAGAAGAAGAA…).  FRDA patients have anywhere from 66 to over 1,700 repeats.    To understand how the GAA trinucleotide expansion leads to FRDA, researchers looked at X25 gene expression by extracting RNA from affected and unaffected patients and doing a northern blot analysis (see the figure below): In panel “a,” the researchers used a probe to detect X25 mRNA. In panel “b,” the researchers used a probe on a duplicate of the original blot to detect human GAPDH mRNA (GAPDH is an enzyme involved in glycolysis).     The sample labeled “YR” is mRNA from yeast cells that was used as a control.    Explain…