Exam 14: Organellar Inheritance

Two parents produced two embryos through in vitro fertilization.One of these embryos was found to have a normal genotype,and the other was found to be a heterozygous carrier for cystic fibrosis.These parents chose to have both placed in the womb.Use of the carrier embryo increased their chance of having a child,and they were willing to pass on a harmful allele to satisfy their own desire to procreate.Based on your knowledge of genetic disease,what would you say about the ethics of their decision?

If a PCR amplified sample hybridizes with two allele specific probes,one normal and one mutant sequence,a carrier is identified if

Quantitative traits can be distinguished by

A DNA sequence can be useful for

The most common method for genotyping allelic SSRs is by

Quantitative trait loci can be examined using pure-breeding parents and measuring a particular trait.If each allele makes an equal contribution to the phenotype,then the number of loci can be discerned.Bristle length in Drosophila behaves as a quantitative trait.If one parent has bristles of 30 nm and a second fly has bristles of 10 nm,then the F1 will have bristles of 20 nm.If the F1 flies are crossed to produce the F2 generation,the following classes of flies are observed.Use this data to answer these questions: a)How many different genotypes would be found among the flies with 10 nm bristles? b).How many different genotypes would be found among the flies with 30 nm bristles? c)How many different genotypes would be found among the flies with 15 or 25 nm bristles? d)How many loci are affecting this trait? e)If one wanted to find a physical marker that was linked to genes affecting bristle length,which flies would be most useful? Number of F2 Flies Length of bristles 10 10 40 15 60 20 40 25 10 30

How many bases can be part of a deletions,duplications,or insertions?

Positional cloning requires knowledge about the

DNA polymerase "stutter," a pause that can cause misalignment of repeating nucleotides,is a main source of variation in microsatellites.

If DNA is isolated from two healthy individuals,it is very likely that their DNA sequence will be identical.

Which of the following is the main source of variation in microsatellites?

Which is the most frequent cause of DNA polymorphism?

Modern geneticists define an allele as any variation in the DNA sequence of a locus.

If the chance of a person being polymorphic for a particular microsatellite is 50%,what is the chance that a person is polymorphic for four unlinked microsatellite loci?

For a gene or a locus to be considered polymorphic it must satisfy the following two conditions must be present in

Incomplete penetrance

The DNA fingerprints of monozygotic twins are identical.

Predisposition to breast cancer results from

Huntington disease is caused by

DNA fingerprints identify polymorphisms in minisatellites and can be used to identify family relationships between old skeletal material and living individuals.