Pedigree chart

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A pedigree chart is a chart which tells you all of the known phenotypes for an organism and its ancestors, most commonly humans, show dogs, and race horses. The word pedigree is a corruption of the French "pied de gru" or crane's foot, because the typical lines and split lines (each split leading to different offspring of the one parent line) resemble the thin leg and foot of a crane.

A genetics pedigree chart following a recessive trait.

1 In animal breeding
2 In human genealogy
- 2.1 U.S. usage
3 See also
4 References
5 External links

[edit] In animal breeding

In an animal pedigree chart, characteristic are coloured in, all those without that characteristic are left unfilled. A disease may be recessive or dominant. Organisms known to be heterozygous are half coloured in, half not. Squares represent males, while circles represent females.

[edit] In human genealogy

Pedigree charts are also a common tool in human genealogy studies as a means of displaying the ancestry of a given individual or the descendants of a given individual. A pedigree chart concentrating on all the ancestors of a single individual (including all female lines of ancestry) is also called a "birth brief" and may number persons on the chart using the Ahnentafel system.

Equally common, however, is the "family tree" form of pedigree chart, which shows the descendants of a particular individual, and thereby highlights sibling and cousin relationships which would not appear on the above form of pedigree chart. A chart on these lines will often concentrate only on the male line of descent, so that the marriages but not the children of female descendants are recorded. In this way, the pedigree will encompass only those who share the same surname.

In addition to the names of the indivdiduals, it is common to include each person's birth date and place, death date and place, and the marriage date and place of each couple.

In England and Wales pedigrees are officially recorded in the College of Arms, which has records going back to the middle ages, including pedigrees collected during roving inquiries by its heralds during the sixteenth and seventeenth century. The purpose of these heraldic visitations was to register and regulate the use of coats of arms. Those who claimed the right to bear arms had to provide proof either of a grant of arms to them by the College, or of descent from an ancestor entitled to arms. It was for this reason that pedigrees were recorded by the visitations. Pedigrees continue to be registered at the College of Arms and kept up to date on a voluntary basis but they are not accessible to the general public without payment of a fee.

More visible, therefore, are the pedigrees recorded in published works, such as Burke's Peerage and Burke's Landed Gentry in the United Kingdom and, in continental Europe by the Almanach de Gotha. Due to space considerations, however, these publications typically use a narrative pedigree, whereby relationships are indicated by numbers (one for each child, a different format for each generation) and by indentations (each generation being indented further than its predecessor). This format is very flexible, and allows for a great deal of information to be included, but it lacks the clarity of the traditional chart pedigree.

[edit] U.S. usage

In the United States, the term "pedigree chart" refers to a chart showing the direct ancestors of a given individual. In addition to the names of the individuals, the chart often includes each person's birth date and place, death date and place, and each couple's marriage date and place. It is also common for persons on the chart to be numbered according to the Ahnentafel numbering system.^[1]

Pedigree chart numbered on the Ahnentafel system
                                            8.  Great-grandfather
                    4. Paternal grandfather-|
                    |                       9.  Great-grandmother
          2. Father-|
          |         |                       10. Great-grandfather
          |         5. Paternal grandmother-|
          |                                 11. Great-grandmother
          |
1. Person-|
          |
          |                                 12. Great-grandfather
          |         6. Maternal grandfather-|
          |         |                       13. Great-grandmother
          3. Mother-|
                    |                       14. Great-grandfather
                    7. Maternal grandmother-|
                                            15. Great-grandmother