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Genealogy is the study and tracing of family pedigrees. This involves collecting the names of relatives, both living and deceased, and establishing the relationships between them based on primary, secondary and/or circumstantial evidence or documentation, thus building up a cohesive family tree.

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Personal Genomics Introduction & Links

Personal genomics is a branch of genomics where individual genomes are genotyped and analyzed using bioinformatics tools. It is also related to traditional population genetics. The genotyping stage can have many different experimental approaches including single nucleotide polymorphism (SNP) chips (typically 0.02% of the genome), or partial or full genome sequencing. Once the genotypes are known, there are many bioinformatics analysis tools that can compare individual genomes and find disease association of the genes and loci. The most important aspect of personal genomics is that it leads to the personal medicine where patients can take genotype specific drugs for medical treatments.

Personal genomics is not a single individual's vision or invention. Many researchers for decades anticipated this biological branch will eventually arrive with minimum cost of genotyping. Due to the advent of cheap and fast sequencers, full genome personal genomics is becoming a reality. However, there have been active early proponents of personal genomics projects such as George Church in Harvard Medical School.

Genomics used to mean academic research on consensus genomes which have been assembled from many different individuals of a particular species. The personal genomics changes this into customized bioinformatic discovery on individuals.

Use of personal genomics in predictive medicine

Predictive medicine is the use of the information produced by personal genomics techniques when deciding what medical treatments are appropriate for a particular individual.

An example of the use of predictive medicine is in selecting which drug to prescribe to a patient. The drug should be chosen to maximize the probability of obtaining the desired result in the patient and minimizing the probability that the patient will experience side effects.

The probabilities of obtaining the desired result and of experiencing side effects are both dependent on information that can be obtained by analysis of the patient’s genome.

Genomics is itself a rapidly developing field. As new techniques are developed in genomics it is likely that some of them will be applied in personal genomics and predictive medicine.

Personal Genome Project
» personalgenomes.org

23andMe
Sells mail order kits for SNP genotyping. The $399 kit contains everything a patient needs to take their own saliva sample. The patient then mails the sample to 23andMe who carry out microarray analysis on it. This provides genotype information for about 600,000 SNPs. This information is used to estimate the genetic risk of the patient for over 80 diseases as well as ancestry analyses.
» 23andme.com

Illumina
Focused on commercializing full genome sequencing but are not involved in the predictive medicine (interpretative) side.
» everygenome.com

deCODE Genetics
Charges $985 to carry out genotyping of approximately 1 million SNPs and provides risk estimates for 29 diseases.
» decodeme.com

Navigenics
began offering SNP-based genomic risk assessments as of April 2008. Navigenics is medically focused and emphasizes a clinician's and genetic counselor's role in interpreting results. Currently over 20 disease are offered for $2500. Navigenics uses Affymetrix Genome-Wide Human SNP Array 6.0 , which genotypes 900,000 SNPs.
» navigenics.com

Knome
Provides full genome (98% genome) sequencing services for $99,500.
» knome.com

Complete Genomics
» completegenomicsinc.com

Sequenom Center for Molecular Medicine
» scmmlab.com

The Business of Personal Genomes

In some ways, Jorge Conde, cofounder of the genomics startup Knome, knows his clients more intimately than any other company president. Knome is the first company to sequence and analyze a consumer's complete genome. And Conde and his team have spent a full day with each member of their select clientele, going through the minute details of the results in search of hidden genomic time bombs, subtle health risks, and other information.

At $100,000, Knome's product is still out of reach for most consumers. But that could change fast. The cost of genome sequencing is dropping by an order of magnitude every one to two years, and the cost of Knome's product will drop with it, though not quite as fast. (When the company debuted its service in late 2007, it cost $350,000.) That means that within the next few years, having your genome sequenced will cost about the same as cataract surgery, making it affordable to include your genome sequence as an integral part of your medical record.

» Technology Review [ Contribute: submit link / submit article ]
» Knome

Tree Of Me Genealogy

With the discovery that a person's DNA contains information that has been passed down relatively unchanged from our earliest ancestors, analysis of DNA is just beginning to be used for genealogical research. There are two DNA types of particular interest. One is the mitochondrial DNA which we all possess and which is passed down with only minor mutations through the female line. The other is the Y-chromosome, present only in males, which is passed down with only minor mutations through the male line.

Genealogical DNA Test

A genealogical DNA test involves examining the nucleotides at specific locations on a person's DNA. The test results have no medical value and cannot determine genetic diseases or disorders; they are only used for genetic genealogy.

How a test is done

A genealogical DNA test is generally done by taking a painless cheek-scraping at home and mailing the sample to a genetic genealogy laboratory for testing. Some laboratories use mouth wash or chewing gum. Certain laboratories store DNA samples for ease of future testing whereas others destroy them, guaranteeing that a sample is not available for further analysis.

Types of tests

Genealogical DNA tests allow one to identify their recent and far distant ethnic and geographic origins. Most commonly, one uses Y chromosome (Y-DNA) testing and mitochondrial DNA (mtDNA) testing. Y-DNA and mtDNA tests are by far the most common and often people refer to them as the only genealogical DNA tests. However, additional tests are available for distant and recent ethnic origins.

Y chromosome (Y-DNA) testing
  A man's paternal ancestry can be traced using the DNA on his Y chromosome (Y-DNA). Women who wish to determine their paternal ancestry can ask their father, brother, paternal uncle, paternal grandfather, or a cousin who shares the same paternal lineage to take a test for them (i.e. any male family member who has the same surname as her father).

What gets tested
  Y-DNA testing involves looking at segments of DNA on the Y chromosome (found only in males) where sequences of nucleotides repeat, known as short tandem repeats (STRs). These segments are considered "junk" DNA. The segments which are examined are referred to as markers and are designated by a DYS number (DNA Y-chromosome Segment number).

Understanding test results
  A Y-DNA test will look at 10-43 markers on the Y chromosome. The results will tell how many repeats the test subject had at any given marker; the variations of repeats are known as alleles. For example, at DYS455, the results will show 8, 9, 10, 11 or 12 repeats (source). The test results are then compared to another person's results to determine the time frame in which the two people shared a most recent common ancestor (MRCA). If the two tests match on 37 markes, there is a 50% probability that the MRCA was less than 5 generations ago and a 90% probability that the MRCA was less than 17 generations ago.

Records in genealogical research

Records of persons who were neither royalty nor nobility began to be taken by governments in order to keep track of their citizens. (In most of Europe, for example, this started to take place in the 16th century.) As more of the population began to be recorded, there were sufficient records to follow a family using the paper trail they left behind.

As each person lived his or her life, the major events were documented with a license, permit or report which was sent to a local, regional or national office or archive. A genealogist locates copies of these records, wherever they have been stored, and rearranges the information about each person to discover family relationships and recreate a timeline of each person's life once again.

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• Genealogical Research
• Family Tree

Records that are used in genealogy research include:

• Adoption records
• Baptism or christening records
• Biographies and biographical profiles (as in Who's Who, etc.)
• Birth records
• Cemetery records and tombstones
• Census records
• City directories and telephone directories
• Daughters of the American Revolution records
• Death records
• Diaries, personal letters and family Bibles
• Emigration, immigration and naturalization records
• Land and homestead records, deeds
• Marriage and divorce records
• Medical records
• Military records
• Newspaper columns
• Obituaries
• Occupational records
• Oral history
• Passports
• Photographs
• School and alumni association records
• Ship passenger lists
• Social Security records
• Tax records
• Voter registration records

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