What is the function of satellite DNA?
Satellite DNA contributes to the essential processes of formation of crucial chromosome structures, heterochromatin establishment, dosage compensation, reproductive isolation, genome stability and development.
What is the role of satellite DNA in DNA fingerprinting?
Satellite DNA shows polymorphism which forms the basis of DNA fingerprinting. There are short nucleotide repeats in the DNA which are specific in each individual and vary in number from person to person but are not inherited. These are called ‘variable number tandem repeats’ or mini-satellites.
What is alpha satellite sequence?
Alpha satellite is defined by 171-bp monomers that are 50%–70% identical in sequence (Willard 1985). Monomers are typically tandemly arranged, so that a defined number of monomers creates a higher-order repeat (HOR) array.
What are the two types of satellite DNA?
Satellite DNA structure These repeats can be as small as 1−2 bp long or as long as 10−60 bps long. The short tandem repeats (1-2 bp long) are called microsatellite or simple sequence repeats (SSRs), while the longer tandem repeats (10-60bp long) are called minisatellites or variable number tandem repeats (VNTRs).
What is satellite DNA and repetitive DNA?
Repetitive DNA can be divided into two classes: the tandem repetitive sequences (known as satellite DNA) and the interspersed repeats. The term satellite is used to describe DNA sequences that comprise short head-to-tail tandem repeats incorporating specific motifs. Variations in DNA in the genome.
Which satellite DNA is used in DNA fingerprinting?
Minisatellites are the most highly variable sequence element in the human genome and the variable number of tandem repeats (VNTR) is used for DNA fingerprinting analysis in forensic science.
Do centromeres contain alpha satellite sequence?
Satellite DNA, including α satellite DNA found at human centromeres, comprises up to 10% of the genome, but is difficult to study because its repetitive nature hinders contiguous sequence assemblies.
What is satellite DNA explain?
Satellite DNA: DNA that contains many tandem (not inverted) repeats of a short basic repeating unit. Satellite DNA is located at very specific spots in the genome (on chromosomes 1, 9, 16 and the Y chromosome, the tiny short arms of chromosomes 13-15 and 21 and 22, and near the centromeres of chromosomes).
What is meant by satellite DNA?
How can satellite DNA be isolated explain?
Answer: . Satellite DNA is separated from the genomic DNA by density gradient centrifugation; the satellite DNA forms smaller peaks, while the genomic DNA forms a major peak.
How many types of satellite DNA are there?
Satellite DNA families in humans
Satellite family | Size of repeat unit (bp) | Location in human chromosomes |
---|---|---|
α (alphoid DNA) | 170 | All chromosomes |
β | 68 | Centromeres of chromosomes 1, 9, 13, 14, 15, 21, 22 and Y |
Satellite 1 | 25-48 | Centromeres and other regions in heterochromatin of most chromosomes |
Satellite 2 | 5 | Most chromosomes |