The first widely used algorithm for database similarity searching.
The program looks for optimal local alignments by scanning the
sequence for small matches called "words". Initially,
the scores of segments in which there are multiple word hits
are calculated ("init1"). Later the scores of several
segments may be summed to generate an "initn" score.
An optimized alignment that includes gaps is shown in the output
as "opt". The sensitivity and speed of the search
are inversely related and controlled by the "k-tup"
variable which specifies the size of a "word". (Pearson
and Lipman) (NCBI)
Filial generation (F1, F2)
Each generation of offspring in a breeding program, designated
F1, F2, etc. (ORNL)
Filtering
Also known as Masking. The process of hiding regions of (nucleic
acid or amino acid) sequence having characteristics that frequently
lead to spurious high scores.
See SEG and DUST.
(NCBI)
Fingerprinting
In genetics, the identification of multiple specific alleles
on a person's DNA to produce a unique identifier for that
person.
See also: forensics (ORNL)
High-quality, low error, gap-free DNA sequence of the human
genome. Achieving this ultimate 2003 HGP goal requires additional
sequencing to close gaps, reduce ambiguities, and allow for
only a single error every 10,000 bases, the agreed-upon standard
for HGP finished sequence.
See also: sequencing, draft
sequence (ORNL)
Flow cytometry
Analysis of biological material by detection of the light-absorbing
or fluorescing properties of cells or subcellular fractions
(i.e., chromosomes) passing in a narrow stream through a laser
beam. An absorbance or fluorescence profile of the sample is
produced. Automated sorting devices, used to fractionate samples,
sort successive droplets of the analyzed stream into different
fractions depending on the fluorescence emitted by each droplet.
(ORNL)
Flow karyotyping
Use of flow cytometry to analyze and separate chromosomes
according to their DNA content. (ORNL)
Fluorescence in situ hybridization (FISH)
A physical mapping approach that uses fluorescein tags to
detect hybridization of probes with metaphase chromosomes and
with the less-condensed somatic interphase chromatin. (ORNL)
Folded leaf
A layer of alpha-helices wrapped around a single hydrophobic
core but not with the simple geometry of a bundle. (SCOP)
The use of DNA for identification. Some examples of DNA use
are to establish paternity in child support cases; establish
the presence of a suspect at a crime scene, and identify accident
victims. (ORNL)
Siblings born at the same time as the result of fertilization
of two ova by two sperm. They share the same genetic relationship
to each other as any other siblings.
See also: identical twin (ORNL)
Full gene sequence
The complete order of bases in a gene. This order determines
which protein a gene will produce. (ORNL)
