View full lesson: http://ed.ted.com/lessons/james-watson-on-how-he-discovered-dna Nobel laureate James Watson opens TED2005 with the frank and funny story of how he and his research partner, Francis Crick, discovered the structure of DNA. Talk by James Watson.

Transcription is the process by which the information in DNA is copied into messenger RNA (mRNA) for protein production. Originally created for DNA Interactive ( http://www.dnai.org ). TRANSCRIPT: The Central Dogma of Molecular Biology: "DNA makes RNA makes protein" Here the process begins. Transcription factors assemble at a specific promoter region along the DNA. The length of DNA following the promoter is a gene and it contains the recipe for a protein. A mediator protein complex arrives carrying the enzyme RNA polymerase. It manoeuvres the RNA polymerase into place... inserting it with the help of other factors between the strands of the DNA double helix. The assembled collection of all these factors is referred to as the transcription initiation complex... and now it is ready to be activated. The initiation complex requires contact with activator proteins, which bind to specific sequences of DNA known as enhancer regions. These regions may be thousands of base pairs distant from the start of the gene. Contact between the activator proteins and the initiation-complex releases the copying mechanism. The RNA polymerase unzips a small portion of the DNA helix exposing the bases on each strand. Only one of the strands is copied. It acts as a template for the synthesis of an RNA molecule which is assembled one sub-unit at a time by matching the DNA letter code on the template strand. The sub-units can be seen here entering the enzyme through its intake hole and they are joined together to form the long messenger RNA chain snaking out of the top.

Address of the bookmark: http://www.ub.edu/dnasp/

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)

DNA:

Nucleotide Code: Base:

---------------- -----

A.................Adenine

C.................Cytosine

G.................Guanine

T (or U)..........Thymine (or Uracil)

R.................A or G

Y.................C or T

S.................G or C

W.................A or T

K.................G or T

M.................A or C

B.................C or G or T

D.................A or G or T

H.................A or C or T

V.................A or C or G

N.................any base . or -............gap

Protein:

Amino Acid Code: Three letter Code: Amino Acid:

---------------- ------------------ -----------

A.................Ala.................Alanine

B.................Asx.................Aspartic acid or Asparagine

C.................Cys.................Cysteine

D.................Asp.................Aspartic Acid

E.................Glu.................Glutamic Acid

F.................Phe.................Phenylalanine

G.................Gly.................Glycine

H.................His.................Histidine

I.................Ile.................Isoleucine

K.................Lys.................Lysine

L.................Leu.................Leucine

M.................Met.................Methionine

N.................Asn.................Asparagine

P.................Pro.................Proline

Q.................Gln.................Glutamine

R.................Arg.................Arginine

S.................Ser.................Serine

T.................Thr.................Threonine

V.................Val.................Valine

W.................Trp.................Tryptophan

X.................Xaa.................Any amino acid

Y.................Tyr.................Tyrosine

Z.................Glx.................Glutamine or Glutamic acid

Address of the bookmark: https://github.com/lh3/ropebwt2

DeepVariant is an analysis pipeline that uses a deep neural network to call genetic variants from next-generation DNA sequencing data. DeepVariant relies on Nucleus, a library of Python and C++ code for reading and writing data in common genomics file formats (like SAM and VCF) designed for painless integration with the TensorFlow machine learning framework.

https://ai.googleblog.com/2017/12/deepvariant-highly-accurate-genomes.html

https://www.biorxiv.org/content/10.1101/092890v6

Address of the bookmark: https://github.com/google/deepvariant

During the first phase of ENCODE, published in 2007, microarray-based technologies were used to detect regions associated with transcription factors, certain histone modifications and open chromatin within a pre-specified 1% of the human genome.

ENCODE’s second phase saw a switch to sequencing-based technologies, the addition of new assay types and the analysis of functional elements genome-wide, described in a collection of research articles in 2012.

The Encyclopedia paper of ENCODE 3, published in Nature, gives an overview of the various assays that were performed in human and mouse cell lines and tissues and describes a Registry of human and mouse candidate cis-regulatory elements (cCREs).

More at https://www.nature.com/immersive/d42859-020-00027-2/index.html

Metabuli is metagenomic classifier that jointly analyze both DNA and amino acid (AA) sequences. DNA-based classifiers can make specific classifications, exploiting point mutations to distinguish close taxa. AA-based classifiers have higher sensitivity in detecting homology between query and reference sequences, leverageing higher conservation of AA sequences. Metabuli combines the information of both sequence types using a novel k-mer structure, metamer, to enable both specific and sensitive characterization of metagenomic samples. In addition, it can classify reads against a database of any size as long as it fits in the hard disk.

Address of the bookmark: https://github.com/steineggerlab/Metabuli