General Topics

DNA Tools

DNA has become an important part of genealogical research, and Family Historian has a number of tools which can be used to help you work with DNA data. These include diagrams and queries, and other tools.  None of the diagrams or queries listed here, require that you have done any DNA testing, or that you have any DNA information about anyone.  Rather, they show you what you should expect to find, in terms of shared DNA and DNA matches, if the information you have recorded within Family Historian is correct.  Bear in mind that if you record that one person is the child of another, Family Historian will assume that the child is a birth child unless you specify otherwise by indicating that the child is adopted, fostered, step or de facto (de facto means that the person was accepted as the natural child of a parent, even if in fact they weren't).   See also How to Record Birth Parents Correctly for DNA Purposes.

If you have DNA data, and if the information in a diagram or query conflicts with the DNA data you have, this indicates that further investigation is needed to work out where, and in what way the error has occurred. Most likely, some part of your recorded information is incorrect. For example, a person who is recorded as a birth child of a parent, may in fact be the birth child of someone else.

If you have some matching DNA information for two people, you may also be able to use some of the tools provided here, to help you work out how they are related.  For example, if they share X-DNA, you could use the Overlapping X Chromosome diagram to work out which side of the family, they must both belong to.

The Family Historian DNA tools are these:

DNA Diagrams

DNA Flags

DNA Queries

DNA Attributes

DNA Diagram Tools

Diagram Tools are described in more detail below.  In summary, they consist of the following items:

Advanced DNA Tools


DNA Diagrams

Shared Y Chromosome

Only males have a Y-chromosome.  The Y-chromosome is transmitted from father to son nearly unchanged.  The Shared Y Chromosome diagram requires the selection of a male person, and shows the people who should share a Y-chromosome with that selected person if the information about their relationships recorded within Family Historian is correct.

The diagram also shows the appropriate DNA Flags below each person.

  Shared Mitochondrial DNA

DNA exists within a cell's nucleus - but that is not the only place within a cell that DNA can be found.  Cells contain specialized structures called mitochondria, which generate power for the cell (they are sometimes compared to batteries).  Mitochondria also contain DNA.  For human beings, their nuclear DNA (DNA from the cell nucleus) comes from both of their parents.  But everyone, male or female, gets their mitochondrial DNA from their mother alone - and mitochondrial DNA is highly conserved during transmission (not much subject to mutation).  This means that mitochondrial DNA is a useful way of tracing maternal lineage.

The Shared Mitochondrial DNA diagram shows, for a given selected person, male or female, who they should share mitochondrial DNA with, if the information about their relationships recorded within Family Historian is correct. 

The diagram also shows the appropriate DNA Flags below each person.

Overlapping X Chromosome

Males have a single X-chromosome which they receive from their mother.  Females have two X-chromosomes, one of which comes from their mother,  In both cases, these are subject to random recombination at each generation, which means that although the X-chromosome comes from the mother, it is unlikely to be an exact match of either of the mother's X chromosomes, but rather will have parts of both of the mother's own X-chromosomes.

Daughters inherit one of their X-chromosomes from their father; and as the father only has one X-chromosome, this will be passed down pretty much unchanged.

Although X-chromosome inheritance is more complicated than either mitochondrial DNA inheritance or Y-chromosome inheritance, it can nevertheless be useful for tracing and narrowing down possible ancestral lines.  The Overlapping X Chromosome diagram shows, for a given selected person, male or female, who they should share some parts of their X-chromosome with, if the information about their relationships recorded within Family Historian is correct.

The diagram also shows the appropriate DNA Flags below each person.

 atDNA Shared Autosomal DNA (Blood Relatives)

Each person has 23 pairs of chromosomes.  Of these, one pair - the X and Y chromosomes - together determine a person's sex.  The DNA in the other 22 pairs of chromosomes is called autosomal DNA.  Autosomal DNA is inherited equally from both parents. For any given blood relatives, it is possible to calculate what percentage of autosomal DNA, they are likely to share.  This figure is not completely accurate - in fact it becomes less and less accurate the more generations separate the people concerned.  Nevertheless, it too can be used for genealogical purposes.  If you know that two people share a certain percentage of autosomal DNA, you can compare this with what you would expect, given what you have recorded about them within Family Historian.  For a given selected person, male or female, the Shared Autosomal DNA diagram shows all of the people who, if the information about their relationships recorded within Family Historian is correct, should share autosomal DNA with them.  Each box in the diagram includes a description of the relationship between that person and the selected person, and the approximate percentage of autosomal DNA that they could be expected to share.  So, for example, the box for the brother of the selected person will show the brother's name, and below that the word 'brother', and, on the next line, "50% atDNA" - indicating that the brother shares approximately 50% of his autosomal DNA with the starting person.

Sometimes people have more than one relationship.  For example, two people may be cousins twice over, if both of their parents were siblings.  If a person is related in more than one way, all the relationships will be listed on separate lines.  'Double cousins' would show as  "cousin and cousin".  Where people have more than one blood relationship, this will affect the percentage of autosomal DNA that they share.  Ordinary first cousins share 12.5% of their autosomal DNA.  Double cousins share 25% of their autosomal DNA.

The diagram also shows the appropriate DNA Flags below each person.


DNA Flags

The following flags are used in the DNA diagrams, and in other diagrams that use the DNA Flags preset:


 Person shares a Y chromosome (also known as 'Y-DNA') with the starting person

Person shares some part of their X chromosome (also known as 'X-DNA') with the starting person.
mtDNA
 Person shares mitochondrial DNA (also known as 'mtDNA') with the starting person

Person is a half-blood relation of the starting person.  That is to say, they are neither a direct line ancestor or descendant of the starting person, but they share a common ancestor.  Most relatives who are not direct line ancestors or descendants of one another, share 2 common ancestors.  Siblings, for example, most commonly share both parents.  A half-blood relation shares one only.  If two people are related in multiple ways, they will only be considered to be half-blood relations if their closest blood relationship is a half-blood relationship.

Person is a blood relation of the starting person.  Another way of putting the same thing is that they share some part of their autosomal DNA (also known as atDNA) with the starting person.  Anyone who has any of the other 4 DNA flags must also have the blood relation flag.  You can however have the blood relation flag without necessarily having any of the other 4 DNA flags.



DNA Queries

The 4 DNA queries all take a single parameter, which is a starting person.  All of them show relatives (not necessarily all relatives) of the starting person.  And all of them show the following columns:

DNA - Shared Y Chromosome

See the description for the Shared Y Chromosome diagram above.  This query shows the same information but in the form of a tabular result set.

DNA - Shared Mitochondrial DNA

See the description for the Shared Mitochondrial DNA diagram above.  This query shows the same information but in the form of a tabular result set.

Overlapping X Chromosome

See the description for the Overlapping X Chromosome diagram above.  This query shows the same information but in the form of a tabular result set.

Shared Autosomal DNA (Blood Relatives)

See the description for the Shared Autosomal DNA diagram above.  This query shows the same information but in the form of a tabular result set.


DNA Attributes

If you have DNA information for a given person that you wish to record within Family Historian, we recommend that you do this by adding a DNA attribute for that person, providing summary details of DNA testing done by that person in the attribute value field, and storing the full details in a note attached to that attribute.  Family Historian provides an attribute called DNA Markers which is designed to be used for this purpose.  To add this attribute for a given person, open that person's record in the Property Box and click the Add Fact button on the Facts tab.  Choose More Fact Types... to open the Fact Types dialog.  Select DNA Markers from the list and click Add. If you can't see DNA Markers in the list, it is probably hidden, in which case you need to unhide it.  To do this, click More >> and then tick the Show Hidden checkbox. You should now see DNA Markers in the list.  To ensure that it remains visible in the future, select it, click Edit, untick the Hidden checkbox (bottom right), and press OK. 

If a fact type is marked as 'hidden', this does not mean that facts of that type will not appear in reports.  It is just a convenient way of ensuring that fact types you never use do not appear in lists (making it easier to find the ones you do use - see Fact Definition dialog for more on this).  However, it may well be that you do not want the DNA Markers attribute to appear in most reports.  If you wish to exclude it, you can mark it as Private.  By default, attributes marked as 'Private' are excluded from most reports (unless you override this).  Another strategy would be to include the DNA Attribute in reports but exclude the actual DNA data stored in the note attached to the attribute.  To do that, you can mark the note contents as private.  You do this by adding two opening square brackets [[ at the start of the note, and two closing square brackets ]] at the end of the note.


DNA Diagram Tools

Family Historian diagrams can use icons to show particular features - such as if a person has a Y-chromosome or Mitochondrial DNA in common with a given starting person.  All of the DNA diagrams listed on this page show these icons, but you can also include the same icons in other diagrams if you wish.  One way to do this is to use the 'DNA Flags' preset.  To select this preset for a given diagram, open Diagram Options, and click the Presets button on the Boxes tab.  From the dropdown menu that appears, choose DNA Flags.  You can use the set of conditions and features used in this preset as examples if you wish to combine some aspects of this preset with other conditions and features.

The DNA Flags preset uses 5 different icons which are taken from a collection of icons which are designed for use with DNA information.  If you wish to associate one of these icons with a particular condition (as illustrated by the DNA Flags preset), create the condition by clicking << Add Condition in the Boxes tab of Diagram Options.  Then on the Box Features dialog, tick the Icon checkbox and click the Select button that appears. On the Select Icon dialog, set the Category field at the top to 'DNA' to view DNA-related icons, available for you to select.

To learn more, see Diagram Options Dialog: Boxes Tab.

The Shared Autosomal DNA diagram shows the rough percentage of autosomal degree that each person shares with the diagram root.  You can show this same information by choosing the DNA Relatedness text scheme.  Text schemes can be created or edited on the Text tab of Diagram Options.  You can also add DNA Relatedness to any other text scheme.  It is one of the available items listed on the left-hand side when you edit a text scheme.  To learn more about text schemes, see Diagram Options Dialog: Text Tab.