genome
all of the chromosomes and DNA sequences that an organism can possess.
genomics
the molecular analysis of an entire genome of a species.
structural genomics
the branch of genomics that determines the three-dimensional structures of proteins.
functional genomics
the study of gene function at the genome level. It involves the study of many genes simultaneously.
proteomics
the study of protein function at the genome level. It involves the study of many proteins simultaneously.
mapping
the experimental process of determining the relative locations of genes or other segments of DNA along individual chromosomes.
cytogenetic mapping
the mapping of genes or genetic sequences using microscopy
linkage mapping
the mapping of genes or other genetic sequences along a chromosome by analyzing the outcome of crosses
physical mapping
the mapping of genes or other genetic sequences using DNA cloning methods.
genetic map
any method used to determine the linear order of genes as they are linked to each other along the same chromosome. this term is also used to describe the use of genetic crosses to determine the linear order of genes.
chromosome map
a chart that depicts the linear arrangement of genes along a chromosome
locus
the physical location of a gene within a chromosome
in situ hybridization
a technique used to cytologically map the locations of genes or other DNA sequences within large eukaryotic chromosomes. in this method, a complementary probe is used to detect the location of a gene within a set of chromosomes.
FISH (fluorescence in situ hybridization)
a form of in situ hybridization in which the probe is fluorescently labeled.
chromosome painting
the use of probes to identify particular regions of chromosomes. the probes are usually assigned a computer-generated color.
molecular marker
a segment of DNA that is found at a specific site in the genome and has properties that enable it to be uniquely recognized using molecular tools such as a gel electrophoresis.
polymorphic
a term used to desrive a trait or gene of that is found in population
RFLPs (restriction fragment length polymorphisms)
genetic variation within a population in the lengths of DNA fragments are digested with particular restriction enzymes.
monomorphic
a term used to describe a gene that is found as only one allele in a population.
lod (logarithim of the odds) score method
a method that analyzes pooled data from alarge number of pedigrees or crosses to determine the probability that two genetic markers exhibit a certain degree of linkage.a lod score value >/= 3 is usually accepted as strong evidence that two markers are lin
RFLP map
a genetic map composed of many RFLP markers
microsatellites
short simple sequences (typically a couple hundred base pairs in length) that are interspersed throughout a genome and are quite variable in length among different individuals. they can be amplified by PCR.
STRs (short tandem repeats)
short DNA sequences that are repeated many times ina row. often found in centromeric and telomeric regions.
STS (sequence tagged site)
a short segment of DNA, usually between 100 and 400 bp long, the base sequence of which is found to be unique within the entire genome. these are identified by PCR.
founder
with regard to genetic diseases, an individual who lived many generations ago and was the person in which a genetic disease originated.
contig
a series of clones that contain overlapping pieces of chromosomal DNA.
artificial chromosomes
cloning vectors that can accommodate large DNA inserts and behave like chromosomes when inside of living cells.
YAC (yeast artificial chromosome)
a cloning vector propagated in yeast that can reliably contain very large insert fragments of DNA.
BACs (bacterial artificial chromosomes)
a cloning vector that propagates in bacteria and is used to clone large fragments of DNA.
PACs (P1 artificial chromosomes)
an artificial chromosome developed from P1 bacteriophage chromosomes.
cosmid
a vector that is a hybrid between a plasmid vector and phage lambda. cosmid DNA can replicate in a cell like a plasmid or be packaged into a protein coat like a phage. cosmid vectors can accept fragments of DNA that are typically tens of thousands of base
positional cloning
a cloning strategy in which a gene is cloned based on its mapped position along a chromosome.
chromosome walking
a common method used in positional cloning in which a mapped gene or RFLP marker provides a starting point to molecularly "walk" toward a gene of interest via overlapping clones.
subcloning
the procedure of making smaller DNA clones form a larger one.
PFGE (pulsed-field gel electrophoresis)
a method of gel electrophoresis used to separate small chromosomes or very large pieces of chromosomes.
genome sequencing projects
research endeavors that have the ultimate goal of determining the sequence of DNA bases of the entire genome of a given species.
hierarchial shotgun sequencing
a genome sequencing strategy in which small DNA fragments are mapped prior to DNA sequencing.
whole-genome shotgun sequencing
a genome sequencing strategy that bypasses the mapping step. the whole genome is subjected to shotgun sequencing.
double-barrel shotgun sequencing
a type of shotgun sequencing in which DNA fragments are randomly sequenced from both ends.
Human Genome Project
a worldwide collaborative project that provided a detailed map of the human genome and obtained a complete DNA sequence of the human genome.
high-throughput sequencing
rapid DNA sequencing on a micro scale in which many fragments of DNA are sequenced in parallel
next-generation sequencing technologies
newer DNA sequencing technologies that are more rapid and inexpensive
pyrosequencing
a type of next-generation DNA sequencing
SBS (sequencing by synthesis)
a next-generation form of DNA sequencing in which the synthesis of DNA is directly monitored to deduce the base sequence.
comparative genomics
uses information from genome projects to understand the genetic variation between different populations and evolutionary relationships among different species.
PCR (polymerase chain reaction)
DNA is copied multiple times to produce many copies of the original molecules helpful when there's only a small DNA sample
EcoRI
a restriction enzyme that specifically cuts DNA with sequence GAATTC and creates sticky ends