|
A |
Allele
Alternative versions of a
gene or other segment of a chromosome |
| |
Alternative splicing
Different ways of combining a gene's exons to make variants of
the complete protein |
| |
Amplification
Repeated copying of a
piece of DNA |
| |
Annotate
Identify the locations and
coding regions of genes in a genome and determine what they do |
| |
Assembly
Putting sequenced
fragments of DNA into their correct chromosomal positions |
| |
|
|
B |
BAC
Bacterial artificial
chromosome: bacterial DNA spliced with a medium-sized fragment of a
genome (100 to 300 kb) to be amplified in bacteria and sequenced |
| |
Bioinformatics
The study of genetic
and other biological information using computer and statistical
techniques |
| |
BLAST
A computer program that
identifies homologous genes in different organisms, such as human,
fruit fly, or nematode |
| |
|
|
C |
Centimorgan (cM)
A unit of genetic
distance, determined by how frequently two genes on the same
chromosome are inherited together |
| |
Centromere
The
difficult-to-sequence central region of a chromosome |
| |
Coding DNA
Sequences transcribed
into protein structures; also called exons |
| |
Contig
Contiguous sequence of DNA
created by assembling overlapping sequenced fragments of a
chromosome ( whether natural or artificial, as in BACs ) |
| |
Cosmid
DNA from a bacterial virus
spliced with a small fragment of a genome (45 kb or less ) to be
amplified and sequenced |
| |
|
|
D |
Directed
sequencing
Successively sequencing DNA from adjacent stretches of chromosome |
| |
Draft sequence
Sequence with lower
accuracy than a finished sequence; some segments are missing or in
the wrong order or orientation |
| |
|
|
E |
EST
Expressed sequence tag: a
unique stretch of DNA within a coding region of a gene; useful for
identifying full-length genes and as a landmark for mapping |
| |
Exon
Region of a gene's DNA
that encodes a portion of its protein; exons are interspersed with
noncoding introns |
| |
|
|
F |
Finished sequence
Sequence in which
bases are identified to an accuracy of no more than 1 error in
10,000 and are placed in the right order and orientation along a
chromosome with almost no gaps |
| |
FISH
Fluorescence in situ hybridization: a method for pinpointing
the location of a piece of DNA sequence on a chromosome |
| |
Functional
genomics The
study of genomes to determine the biological function of all the
genes and their products |
| |
|
|
G |
Gene expression
Conversion of the
information encoded in a gene first to messenger RNA and then to a
protein |
| |
Gene prediction
Predictions of
possible genes made by a computer program based on how well a
stretch of DNA sequence matches known gene sequences |
| |
Genetic linkage
map A map of the
relative positions of genes and other regions on a chromosome,
determined by how often loci are inherited together |
| |
Genome
The entire chromosomal
genetic material of an organism |
| |
Genomics
The comprehensive study of
whole sets of genes and their interactions rather than single genes
or proteins |
| |
|
|
H |
Homologous genes
Genes with similar
structures and functions |
| |
|
|
I |
Intron
Region of a gene's DNA
that is not translated into a protein |
| |
|
|
J |
Junk DNA
Stretches of DNA that do
not code for genes; most of the genome consists of so-called junk
DNA |
| |
|
|
K |
Kilobase (kb)
Unit of DNA length equal
to 1000 bases |
| |
|
|
L |
Locus Chromosomal location
of a gene or other piece of DNA |
| |
|
|
M |
Megabase (Mb)
Unit of DNA length equal
to 1 million bases |
| |
|
|
P |
PCR Polymerase chain
reaction: a technique fro amplifying a piece of DNA quickly and
cheaply |
| |
Physical map
A map of the locations of
identifiable markers spaced along the chromosomes; a physical map
may also e a set of overlapping clones |
| |
Plasmid
Loop of bacterial DNA that
replicates independently of the chromosomes; artificial plasmids can
inserted into bacteria to amplify DNA for sequencing |
| |
Polymorphism
A variation in DNA
sequence within a population |
| |
Proteome
The full complement of
proteins produced by a particular genome |
| |
Proteomics
The study of the full
set of proteins encoded by a genome |
| |
Pseudogene
A sequence of DNA
similar to a gene but nonfunctional; probably the remnant of a
once-functional gene that accumulated mutations. |
| |
|
|
R |
Regulatory region
A segment of DNA that
controls whether a gene will be expressed and to what degree |
| |
Repetitive DNA
Sequences of varying
lengths that occur in multiple copies in the genome; it represents
much of the genome |
| |
Restriction enzyme
An enzyme that cuts
DNA at specific sequences of base pairs |
| |
RFLP
Restriction fragment
length polymorphism: genetic variation in the length of DNA
fragments produced by restriction enzymes; useful as markers on maps |
| |
|
|
S |
Scaffold
A series of contigs that
are in the right order but are not necessarily connected in one
continuous stretch of sequences |
| |
Shotgun sequencing
Breaking DNA into many
small pieces, sequencing the pieces, and assembling the fragments |
| |
SNP
Single-nucleotide
polymorphism: common, single-base-pair variation in DNA |
| |
Structural
genomics The
effort to determine the 3D structures of large numbers of proteins
using both experimental techniques and computer simulation |
| |
STS
Sequence tagged site: a
unique stretch of DNA whose location is known; serves as a landmark
for mapping and assemble |
| |
|
|
T |
Telomere
The free end of a
chromosome |
| |
Transcription
factor A protein
that binds to regulatory regions and controls gene expression |
| |
Transcriptome
The full complement of
activated genes, or mRNAs or transcripts in a particular tissue at a
particular time |
| |
|
|
Y |
YAC
Yeast artificial
chromosome: yeast DNA spliced with a large fragment of a genome (up
to 1000 kb) to be amplified in yeast cells and sequenced |
| |
|
|
