The biggest and perhaps most fearsome of the world's big cats, the tiger, shares 95.6 percent of its DNA with humans' cute and furry companions, domestic cats.

The new research showed that big cats have genetic mutations that enabled them to be carnivores. The team also identified mutations that allow snow leopards to thrive at high altitudes.

Reference:

http://www.nbcnews.com/science/your-cat-ferocious-tigers-share-lot-95-6-percent-their-4B11182690

http://timesofindia.indiatimes.com/home/environment/flora-fauna/Gene-mapping-of-tiger-completed/articleshow/22671681.cms

Paper:

http://www.nature.com/ncomms/2013/130917/ncomms3433/full/ncomms3433.html

More @ http://news.yale.edu/2013/10/17/researchers-rewrite-entire-genome-and-add-healthy-twist

News Reference: Yale news

Image Source: Sciencedaily.

The vital metaphase stage of cell division, when the sister chromatids migrated to the centre and lined up in a row, and pulled apart using attached microtubules in such a way that half the DNA ends up in each daughter cell. However, before the mitotic spindle‐mediated movement gets start and pulled DNA apart, the chromosomes are free to undergo recombination which involves the exchange of genetic material either between multiple chromosomes or between different regions of the same chromosome.

During recombination, the precise breakage of each strand, exchange between the strands, and sealing of the resulting recombined molecules happens. The “chromosomal breakpoints” refers to these places where they break. Mostly, this process occurs with a high degree of accuracy at high frequency in both eukaryotic and prokaryotic cells. But occasionally this “break and sealing/ break and reattach” process goes wrong and the reattachment happens in the wrong place which usually create disaster (with few exceptions).These chromosome disaster or abnormalities involve the gain, loss or rearrangement of visible amounts of genetic material during cell division. These abnormalities are of two type, the first one is numerical abnormalities  where severe disorders are caused by the loss or gain of whole chromosomes, which affect the copy number of hundreds or even thousands of genes. The second are structural abnormalities which can be unbalanced or balanced. The former are similar to numerical abnormalities in that genetic material is either gained or lost. The natural defects in chromosome segregation are linked to cancer and several genetic diseases (http://en.wikipedia.org/wiki/List_of_genetic_disorders). Therefore, the enzymes involved in regulating cell division are still the attractive drug targets for many diseases.

Apart from certain chromosome abnormalities, these “crossing over” of segments of maternal and paternal chromosomes to form hybrid chromosomes have some evolutionary importance and considered as a driver of genetic variation. Moreover, the chromosome breakage in evolution is considered to be non-random in nature(http://www.ploscompbiol.org/article/info%3Adoi%2F10.1371%2Fjournal.pcbi.0020014). In addition the study of breakpoint regions and non-breakpoint (stable) regions of chromosomes indicates both the regions evolved in distinctly different ways ( http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2675965/). These breakage may lead to genetic diseases or participate to chromosomal rearranmgnets and contributed in development of new species.

I will try to explain the genome hotspots/Evolutionary Breakpoint Regions(EBRs)/fragile regions/weak fragments/  in my next blog.

Software for recombination detection:

RAT http://cbr.jic.ac.uk/dicks/software/RAT/

Breakpointer https://github.com/ruping/Breakpointer

DRP http://web.cbio.uct.ac.za/~darren/rdp.html

RB-finder http://www.ncbi.nlm.nih.gov/pubmed/18707535

LDhat2.0 http://ldhat.sourceforge.net/LDhat2.0/instructions.shtml

Reference:

http://www.nature.com/scitable/topicpage/genetic-recombination-514#

Image: Wikipedia , sciencelearn.org.nz

Recommended Articles:

http://www.friendshipcircle.org/blog/2012/05/22/13-chromosomal-disorders-youve-never-heard-of/

http://web.udl.es/usuaris/e4650869/docencia/segoncicle/genclin98/recursos_classe_%28pdf%29/revisionsPDF/chromosyndromes.pdf

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2775595/table/T2/

http://learn.genetics.utah.edu/content/disorders/chromosomal/

http://www.ncert.nic.in/html/learning_basket/biology/cc&cd.pdf

More at file:///home/urbe/Downloads/diamond_manual.pdf

http://www.nature.com/nmeth/journal/v12/n1/full/nmeth.3176.html

Address of the bookmark: https://github.com/bbuchfink/diamond

Testing for similarities between DNA (deoxyribonucleic acid) samples from two people allows family relationships to be established – or disproved – to an extraordinarily high degree of certainty. A common use for a DNA test is to establish if a man is the biological father of a child; this is known as a paternity test. However, there are other uses for the science of DNA testing (also called genotyping), these include forensic analysis of human DNA samples, and tracking relationships amongst domesticated animals.

The order in which the bases occur in DNA is referred to as the DNA sequence. Each person is unique and just as people differ in their fingerprints, they also have a unique and slightly different DNA sequence. Half of a person’s DNA is received from their mother, and half is received from the father. However, while fingerprints have no value for establishing family relationships, the minor variations in DNA sequence are extraordinarily useful for this purpose. All cells of our body contain DNA, skin cells from the lining of the cheek provide a simple and convenient source of material.

DNA is purified from these cells and the minor variations are read out as a type of bar-code by a machine. When the net DNA ‘barcodes’ from family members are lined up next to each other it becomes clear when a child is related to biological parents because half the stripes in the bar-code like signature will line up with those of the mother, and half will line up with those of the father. On the other hand, in the absence of a biological relationship, the DNA signatures from a child and from a potential parent are not found to have 50% in common. It may be appreciated that DNA testing is the most convenient and scientifically accurate method of determining relationships between people.

Following are the list of companies who qssist in DNA testing:

DNA testing companies

• 23andMe (admixture, adoption, deep ancestry, genealogy) (health and trait reports also available in some countries)
• 24 genetics (admixture, exome sequencing, health, paternity, pharmacogenetics, whole genome sequencing) A company catering for the Spanish market
• African Ancestry (deep ancestry)
• AfricanDNA (FTDNA affiliate) (admixture, deep ancestry, genealogy)
• AncestrybyDNA (admixture, deep ancestry)
• AncestryDNA, a subsidiary of Ancestry.com (admixture, adoption, genealogy)
• Atlas Biomed (deep ancestry, diet, health and traits, sport) A test catering for the Russian market
• BritainsDNA (formerly Ethnoancestry) (admixture, deep ancestry)
• Centrillion Biosciences (aka TribeCode) (admixture, deep ancestry)
• CymruDNAWales - see BritainsDNA
• Dante Labs (exome sequencing, health, whole genome sequencing) A test aimed at the European market
• DNA Ancestry and Family Origin (FTDNA affiliate in the Middle East) (admixture, adoption, deep ancestry, full mtDNA sequencing, genealogy)
• DNA Consultants (admixture, deep ancestry)
• DNA Tribes (admixture)
• DNA Worldwide (formerly a FTDNA partner. See also Living DNA)
• Ethnoancestry - see BritainsDNA
• Family Tree DNA (admixture, adoption, deep ancestry, full mtDNA sequencing, genealogy, Y chromosome sequencing)
• Full Genomes Corporation (whole genome sequencing, Y-chromosome sequencing)
• Gene by Gene - the parent company of Family Tree DNA which now incorporates the companies previously known as DNA Traits, DNA DTC and DNA Findings (research, health, exome sequencing, whole genome sequencing)
• Genebase (deep ancestry, genealogy)
• GenoTek (admixture, genealogy, diet and fitness, family planning, health, talents and sports) A company catering for the Russian market
• Genographic Project (admixture, deep ancestry)
• Genos Research Inc (DTC whole exome sequencing; consumer focused healthcare big data spin out from Complete Genomics; Note: no genetic genealogy focus or tools)
• Guardiome (admixture, whole genome sequencing and interpretation)
• Helix (exome sequencing) US supplier of the Genographic Project Geno 2.0 Next Generation test
• iGENEA (FTDNA affiliate) (admixture, deep ancestry, genealogy)
• IrelandsDNA - See BritainsDNA (formerly Ethnoancestry)
• MyDNA Global - a new name for BritainsDNA
• Living DNA (admixture, deep ancestry) See also DNA Worldwide
• MyHeritage DNA (admixture, genealogy)
• Oxford Ancestors (deep ancestry)
• Roots for Real (admixture, deep ancestry)
• ScotlandsDNA - (formerly Ethnoancestry) (admixture, deep ancestry)
• Sorenson Genomics (laboratory services)
• Sure Genomics (whole genome sequencing and interpretation)
• TribeCode See Centrillion Biosciences
• Veritas Genetics (whole genome sequencing and interpretation)
• Xcode (Diet and Fitness, Precision medicine, Genotyping, Sequencing, Interpretation)
• YorkshiresDNA - See BritainsDNA (formerly Ethnoancestry)
• WeGene (admixture, deep ancestry, health, sports, traits) A test tailored for the East Asian market
• YSEQ (custom Y-SNPs, Y-STRs, SNP panels, whole genome sequencing)

Detail paper at https://bmcgenomics.biomedcentral.com/articles/10.1186/s12864-017-3927-8

Address of the bookmark: https://github.com/VicugnaPacos/ALPACA

It installs in any computer even if you don't have administrator rights!

Address of the bookmark: http://www.dnabaser.com/download/DNA-Counter/index.html

NucDiff provides information about the types of differences and their locations. It is possible to upload the results into genome browser for visualization and further inspection. It was written in Python and uses the NUCmer package from MUMmer[1] for sequence comparison.

Address of the bookmark: https://github.com/uio-cels/NucDiff

This also includes:

• A2Amapper: ATAC, Assembly to Assembly Comparision tool:
  • Comparative mapping between two genome assemblies (same species), or between two different genomes (cross species).

• Sim4db:
  • Spliced alignment of cDNA and genomic sequences, from the same (sim4) or related (sim4cc) species. Optimized for high-throughput batched alignment.

• LEAFF:
  • LEAFF (ahem, Let's Extract Anything From Fasta) is a utility program for working with multi-fasta files. In addition to providing random access to the base level, it includes several analysis functions.

• Meryl:
  • An out-of-core k-mer counter. The amount of sequence that can be processed for any size k depends only on the amount of free disk space.

Address of the bookmark: https://help.rc.ufl.edu/doc/Kmer

Searcg link https://metagraph.ethz.ch/search 

Pre-print https://www.biorxiv.org/content/10.1101/2020.10.01.322164v4 

Address of the bookmark: https://metagraph.ethz.ch/