Exam 18: Genomics: Genetics From a Whole-Genome Perspective

A significant polymorphic inversion on chromosome 17, the MAPT inversion, is identified by marker SNPs that can now be used to screen large numbers in a population. The inverted region is large and extends for approximately 900 kb. The two haplotypes (one inverted and one not)are each associated with increased risk of a number of neurological conditions. How can the inverted region be used to find the most recent common ancestor of the inversion?

It has been predicted that genes may be involved in smoking initiation and/or current smoking behavior. Previously, large twin and family studies have provided evidence of this and an estimate of heritability (genetic contribution)of 37-55% for initiation and 46-59% for current smoking, depending on gender. A large group of researchers from several institutions composed a pathway- or-systems-based series of studies including SNP analysis, cellular location and protein interaction, replication with other samples, statistical analysis, and bioinformatics. What is a likely result?

Compare and contrast the two approaches to genome sequencing (whole-genome shotgun sequencing and clone-by-clone sequencing).

Which of the following would likely exclude a sequence from being considered as an active gene?

The use of computational approaches to understand DNA sequence information is called _____.

A genome sequence is considered to be complete when all its ________ sequences are included, as well as reasonable amounts of repetitive sequences.

The splicing regulatory protein (SR)identifies exons to be included in mRNA. How might SR proteins regulate alternative splicing?

Mammalian genomes all have a number of genes for globin polypeptides. Several of these genes are functional, but several are never expressed. What are the nonfunctional ones known as?

Interspecific genome studies show us conserved sequences, but intraspecific comparisons identify what?

Transcomplementation is a name sometimes given for a test to see whether a gene from one organism can "rescue" a loss-of-function mutant of a different organism with a homologous gene. To which of the following processes might this term apply?

Which of the following describes genome tiling arrays?

In humans, a large number of genes associated with immune function share sequence similarity and are evolutionarily related. These would be known as what kind of group?

In an experiment designed to analyze the mRNAs present in a cell at a given time in the life cycle, it was found that about 50% of the mRNAs are of one type, less than 20% represent eight other mRNAs, and the rest consist of several thousand different mRNAs. What does this information indicate?

An inherited human disorder, familial dysautonomia, results from a nucleotide mutation in the gene IKAP that is expressed in the nervous system. The decreased IKAP protein leads to abnormal development, and the resulting disease is usually fatal by age 30. The nucleotide change alters splicing. If this change affects only the nervous system and not the immune system, in which the gene is also expressed, what feature must be found in this gene?

The karyotypes of several primate species, such as chimpanzee and gorilla, show two nearly telocentric chromosomes as opposed to the single large metacentric chromosome 2 in humans. Does this demonstrate chromosome breakage or fusion at the time of lineage divergence?

Genome-wide expression patterns can be studied using _____.

The set of transcripts present in a cell or organism is called the _____.

Being able to do a BLAST search, among other things, assumes that you and every other researcher has access to known gene sequences. Some would prefer, however, that such sequence information should be "owned" by their discoverers. What are the pros and cons of such a position?

Very many related genes can be recognized by conserved protein domains. To what gene structures do these domains correlate?

Sequencing of DNA from a community of organisms rather than from a single individual is known as ________.