DNA is the genetic material of all living cells and of many viruses.
DNA is: an alpha double helix of two polynucleotide strands.
The genetic code is the sequence of bases on one of the strands.
A gene is a specific sequence of bases which has the information for a particular protein.
DNA is self-replicating - it can make an identical copy of itself.
Replication allows the genetic information to pass faithfully to the next generation.
Replication occurs during the S (= synthesis) stage of interphase just before nuclear division.
The chromosomes contain 90% of the cells DNA.
10% is present in mitochondria and chloroplasts.
Adenine (A) and Guanine (G) are purine bases Thymine (T) and Cytosine (C) are pyrimidine bases
Hydrogen bonds link the complementary base pairs: o Two between A and T
(A = T) o Three between G and C
C) A single unit in the chain is a nucleotide.
o This consists of a phosphate group,
o a pentose sugar (D = DNA; R = RNA) and
o an organic base
(ATGC = DNA; AUGC = RNA) RNA (RNA = ribonucleic acid) Three different types of RNA, (messenger (mRNA), transfer (tRNA) ribosomal (rRNA))
All are made in the nucleus (transcription)
o ribosomes are synthesised in the nucleolus;
o mRNA prepared there too introns removed All types of RNA are involved in protein synthesis:
o mRNA: copies the information from the DNA.
o tRNA: carries the specific amino acid to the mRNA in contact with the ribosome.o rRNA: makes up 55% of ribosomes (the other 45% = protein).
Some RNA molecules can function as enzymes.Differences between DNA and RNA DNA is double stranded; RNA is a single stranded
N.B.ATP is also a nucleotide, with ribose as the pentose sugar.
DNA contains the pentose sugar deoxyribose; RNA contains the pentose sugar ribose.
DNA has the base Thymine (T) but not Uracil (U); RNA has U but not T.
DNA is very long (billions of bases); RNA is smaller (hundreds to thousands of bases) DNA is self-replicating, RNA is copied from the DNA so it is not self-replicating The genetic information is held within the base sequence along a DNA strand.
A codon is a sequence of three nucleotides, coding for one amino-acid.The genetic code is universal, thus all life must have had a common ancestor (i.e.evolution)
Coding structures (Exons) These are the parts of the DNA that contain the code for the synthesis of protein or RNA.
These coding sequences are present within genes.
This is DNA that does not contain information for the synthesis of protein or RNA.
The non-coding sequences are found both between genes and within genes (= introns).
These non-coding sequences have been termed junk DNA but they: o do play a role in gene expression (i.e.whether a gene is switched on or off) o act as spacer material,
o permit the synthesis of many new proteins and
o play an important role in evolution.
Non-coding DNA makes up 95% of human DNA.
Non-coding DNA segments within genes are called introns.
DNA Replication This takes place during the S stage of interphase Nucleotides are synthesised in huge quantities in the cytoplasm.
An enzyme unzips the two complementary strands of DNA.
New complementary nucleotides link to the exposed bases on the separated strands.
The general name for this group of enzymes is DNA polymerase.A new complementary strand is built along each old strand.
Two DNAs, identical to the original and each other, are now present.
Each new DNA molecule is thus half old and half new
o semi-conservative replication.
Gene - A section of DNA containing a particular sequence of bases that codes for a specific protein.
Protein Synthesis - The transcription of a specific DNA base sequence into mRNA and its translation, by a ribosome, into a particular amino acid sequence forming a protein.
Genetic Code The universal code that determines the function of all possible triplets of DNA / mRNA.
Most triplets specify a particular amino acid (= a codon).
Some triplets function as a start or stop signal for protein synthesis.
It is a degenerate code as a particular amino acid may be coded for by more than one codon.
Process of Protein Synthesis transcription and translation Transcription DNA base sequence to mRNA base sequence The code for the protein is carried by one of the DNA strands in the gene.
An enzyme separates the two DNA strands at the gene locus exposing the gene sequence.
A complementary copy
- mRNA - is made of the gene sequence o new nucleotides form a complementary RNA strand
o using the DNA gene sequence strand as a master o the enzyme RNA polymerase links the new nucleotides forming mRNA.
Uracil (U) is the complementary base to adenine in RNA, thymine (T) is not found in RNA.
The complementary RNA copy is called messenger RNA (mRNA).
The mRNA separates from the DNA strand and passes from the nucleus to the cytoplasm.
Translation mRNA base sequence to amino acid sequence.A ribosome binds to the start point of the mRNA.
The ribosome will decode the mRNA in sets of three bases (a codon).
Each codon specifies a particular amino acid.
The sequence of bases on the mRNA determines the sequence of amino acids in the protein any change = a mutation Two codons of the mRNA are exposed in turn
Two complementary tRNA molecules attach to these two mRNA triplets.
The amino acids of
Your mtDNA Full Sequence ResultsMy FTDNA Code:
_____________ use their mtDNA results for genealogical purposes.For several years our clients have askgenealogical purposes.
Our best (and only) answer has been that the very slow made mtDNA less useful in making solid genealogical comparisons.shown many new mutations that will ultimately allow more precise lineages to be hes of haplogroups.
The haplogroup displayed on your Because it now appears clear that most scientific papers in the future will use mtDNA offer this test for genealogical and We offer this test for
To more accurately establish t To apply statistics to better predict when two people who match likely shared a
To provide the only (or final) mtDNA test that one will ever need to take
To allow our most inquisitive clients to have results in hand when more advanced lished in the future 1Your mtDNA Full Sequence ResultsEnclosed you will find a certificate showing that you have had your mtDNA analyzed by Family Tree DNA.
The results represent your actual DNA sequences differences from the Cambridge Reference Sequence (CRS) and are listed www.familytreedna.comogroups are defined by specific mutations which took place tens of thousands of years ago and have been passed down to all of eep ancestral geographic origins rld map we include with this certificate labels the general regions in which your haplogroup can be found.
We also use arrows to indicate how the haplogroup in the mtDNA Results sectidecade regarding these mutations and haplogroups suggests tochondrial Eve approximately 140,000 years ago in Africa.
Further details may be reviewed in the journal Nature , November 2000; in Science, November 2000 or , etc.
These data are based on what we know so far and will change as we # differences that the MRCA lived this number of that the MRCA was number of that the MRCA was number of 0 9 16 1 25 2 35 3 44 2Your mtDNA Full Sequence Resultsand anthropological study.
For example, mtDNA result, the study of mtDNA is essentially the study of female genetic lines within human populations.
Mutations, when they occur, arUsing proper documentation and historical Mitochondria are present in all human cells and contain their own DNA.
Both males and ss it on to their offspring.
Therefore, from fathers.
The chart below illustrates how mtDNA is Boy Girl Boy Girl Brother Sister Boy Girl > Father Mother Aunt
MtDNA analysis is performed by looking for both similarities and differences among individuals.
We test all of the 16,569 base pairs and use them for genealogical and genetic analysis.
A base pair is a specific component of the DNA and is made of adenine (A) and guanine (G) or cytosine (C) and thymine (T).
Therefore, our report will express your results as a series of letters representing the bases specifically found in your mtDNA.3Your mtDNA Full Sequence ResultsMtDNA results are commonly compared to the CRS, the industry standard which was sequenced in 1981.
Any place in your mtDNA where you have a difference from the CRS is characterized as a mutation.
If your results show no mutations at all it happens when one base is replaced by a different base, when a base is inserted bewhen a base is removed from a position without being replaced.
The letters represent the new code found at that place in the sequence.
A C in position 16154, for example, means that at the 16154th base pair, you have a C in place of the T listed for that position in the CRS.
In most mutations, the base pair switches onlyr example, A always ners with C.
Mutations that switch in this manner tal letter next to the You may see insertions in your mtDNA sepair 255, for example, the insertion will be listed as the base pair and .1C.
In this case, a single base pair insertion has been found in efore denoted with a C.
The insertion then looks like this: 255.1C.
If you have a two base pair insertion the results It is also possible that you have a deletion: a base pair was not copinot have a base pair at that particular place in your sequence.
For example, 424 means that this location, 424, is not in your sequence and is represented by a minus Your analysis highlights these differences other individuals ing to build our database of full sequence
mtDNA and our mtDNAPlus tests.
This o individuals shared a common female http://www.ncbi.nlm.nih.gov/BLAST/ and click on the link which reads Quickly search for highly similar sequences 4Your mtDNA Full Sequence ResultsUseful terms to know: CRS (Cambridge Reference Sequence):her words, any place in your mtDNA where
A deletion takes place when a base DNA (deoxyribonucleic acid):
Known by many as the structure of heredity, DNA is a chemical consisting of a sequence of hundreds of millions of nucleotides found in the
information about an individual and is shaped l unit of heredity passed from parent to offspring.HVR1 and HVR2 (HyperVariable Region 1 and 2):a persons ethnic and geographic origins, as a base pair is added to the sequence.
their mothers mtDNA.
A heritable change that may occur in a gene or chromosome and may take Polymorphism:
A heritable mutation, or It has been a pleasure to serve you.If you have questions, please feel free to email us www.familytreedna.comour ever-expanding Frequently Asked .
Of course we encourage you to visit opportunities we have Family Tree DNA - Genealogy by Genetics, Ltd.1445 North Loop West, Suite 820 Houston, Texas 77008, USAPhone: (713) 868-1438 | Fax: (832) 201-7147 info@FamilyTreeDNA.com 5.
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