Ch 20 Genomics & Proteonomics Flashcards
the study of the organization and sequence of the genetic information contained within a genome providing the basic DNA sequence information that is used in functional and evolutionary studies
structural genomics
map of relative distances between genetic loci, markers, or other chromosome regions
genetic maps
what units are genetic maps measured in?
recombination frequencies (cM or m.u.)
what are the limitations of genetic maps?
the resolution/detail of genetic maps is low
they don’t always accurately correspond to physical distances between genes
map of physical distances between loci
physical maps
what are physical maps measured in?
base pairs
what is restriction mapping and how are physical maps created through restriction mapping?
restriction mapping determines the positions of restriction sites in DNA
A sample of DNA is cut by one restriction enzyme. Another sample of the same DNA is cut by a different restriction enzyme. A third sample of the same DNA is cut by both restriction enzymes. The sizes of the fragments are then compared, and overlap in the sizes are used to position the restriction sites on the original DNA molecule
technique of assembling short sequenced fragments into the correct sequence with the use of genetic and physical maps
map-based sequencing
a set of two or more overlapping DNA fragments that form a continuous stretch of DNA
contig
site in the genome where individual members of a species differ in a single base pair
single-nucleotide polymorphisms (SNPs)
how do SNPs arise?
through mutation
what is required for a variant to be considered an SNP?
the variant must be at least 1% frequent in a population
do SNPs usually produce phenotypic differences?
no, SNPs often do not produce phenotypic differences
what is a haplotype?
a specific set of SNPs on a chromosome
homologous genes found in different species that evolved from a common ancestor
orthologs
