DNA FAQ

We compare the DNA of two people to see if their samples match and, if they do, those two people may be related. If their DNA does not match, we know they are not related. All of your DNA came to you from your parents – half from your mother and half from your father. Most of it is a random “jumble” of fragments from your mother and father, which makes it difficult to tell which ancestor contributed which part. This jumbled DNA is called “autosomal” DNA. There are two components of your DNA which are not jumbled up when passed to the child. Each of them comes from only one parent, the mother or the father, and they are virtually identical to everyone in that maternal or paternal lineage for hundreds or thousands of generations back in time. The type that comes from the mother is mitochondrial DNA (abbreviated mtDNA). The type that comes from the father to his sons is Y-chromosome DNA (abbreviated Y-DNA). Genealogists are now using all forms of DNA to do research into ancestry, but the Y-DNA and mtDNA, in that order, are still the most useful.

Your DNA can be broken down into four types or components, each providing unique assistance to the genealogist. Three of those are found in the nucleus of your cells and one (mtDNA) is found outside the nucleus. The four types are listed in alphabetical order below:

• autosomal DNA – atDNA is the first 22 of your nuclear 23 pairs of chromosomes. It is “recombinant”, meaning each parent provides part of your autosomal DNA – approximately 50% from each. Since it comes from all your ancestors, the number of potential matches is greater than any other type of DNA, but it is also more difficult to research and interpret.

• mitochondrial DNA – everyone has mtDNA, but only the mother passes it to her children (i.e. it is “non-recombinant”). It provides a “signature” for the direct maternal (matrilineal) line. It identifies only one person in each generation, the mother. Its signature will match any of her children or the children of her daughters, etc. It is useful in distant and very ancient genealogy research. A perfect match could share a common ancestor recently to 500-700 years ago.

• Y-chromosome DNA – Only men have a Y chromosome (i.e. it is “non-recombinant”). A Y-DNA test will provide a signature for the direct paternal (patrilineal) line. Like mtDNA, it matches only one person in each generation, the father. Its signature will identify all men patrilineally descended from that father. It is the most precise test, identifying only one person in each generation, and it can be used for recent and very ancient ancestry research. A perfect match can imply a match within one or two generations. Y-DNA is offered in Y-STR and Y-SNP tests.

• X-chromosome DNA – x-DNA is not commonly used due to men not receiving any from their father, producing a confusing view of one’s ancestry. Like autosomal DNA, it is recombinant.

We like to use a process called “triangulation“. In this process, DNA test results from several lines of living descendants (or people who believe they are descendants) of a common ancestor are compared to each other. An analysis of the results can paint a picture of the ancestor’s DNA signature. The most effective and accurate method involves determining signatures of recent ancestors first and then comparing their results to determine the signature of more distant ancestors as we work our way back in time. The accuracy of the results depends on the number of test results available, the distance (in relationship) of the test subjects and the availability of paper trail information (pedigrees) to help in the analysis. We also use the “modal value“, but it can be less accurate if the test results are not evenly obtained from the set of cousins.

No, but your DNA provides clues to help identify them. A Y-DNA or mtDNA test will provide you with a “signature” identifying either your direct paternal or maternal line, respectively. Other forms of DNA data can also help determine if you might be related to someone else. That evidence is combined with traditional forms of evidence to prove the relationship to the other person or persons. Once you identify a relative, your shared knowledge, along with traditional research methods, provides you with more clues to your ancestors. The DNA data – if there are enough people in your group – can indicate when your lines intersect, which narrows the search for the common ancestor. As more people contribute their test results to the study, it is possible to focus the search for a common ancestor to a specific lineage and within a few generations.

You now know more than you did – you have found a researcher to whom you are related. Now it’s time to combine your knowledge of your ancestry and to apply traditional research techniques, e.g. examining where and when your ancestors lived, who they associated with, what they named their children (given names can provide family clues as they are often repeated over generations), etc. and then begin working the courthouses, newspapers, libraries, etc.

You might consider participating in the DNA Project for several reasons:

1. You want to resolve the mystery of an unknown ancestor.
2. You are the last male in your line and want to preserve the DNA for future generations to help with their research.
3. Other researchers need a sample from your family branch to help them in their research.

No, the type of testing done for this test has no medical value.

The Y-DNA data used in our project provides a signature for all males descended from your ancient ancestor. It identifies a large group of related people. The data, by itself, cannot be used to identify any specific person. It must be combined with other information to do that. Your test results are either identical to or very nearly identical to those of all your male relatives who are descended from your distant paternal grandfather. This includes your father and uncles, your distant cousins, your grandfather and granduncles, etc. The answer to the question is “it depends on how much other information is available”.

No. The privacy of your identity and that of your test results are guaranteed by numerous safeguards. See the company’s Privacy and Confidentiality statement.

That depends on how much data you have (i.e. how many markers are being compared and the number that match). The accuracy of an estimate of relationship increases as the number of markers compared increases. A match of 100% at 12 markers could mean the people are siblings or it could mean they share a common ancestor from hundreds of generations ago. A perfect match at 67 markers is a good indication there is a shared common ancestor within only a few generations. DNA is a tool that complements traditional research.

The current number of markers tested are 12, 25, 37, 67 and 111. – The 37 or 67-marker test has proven to be the most useful for our family Project. – A 12-marker test is best suited to tell you whether you are NOT related to another family. If you don’t match at 12 markers, you can be assured there is no recent common ancestor. On the other hand, it is common for people to match at all 12 markers and not be recently related. This is because we are all so closely related. More markers will give a better idea of whether a recent relationship exists (within a reasonable genealogical time frame of 1,000 years or less). – The 25 marker test can be a good indicator whether a recent relationship exists. – The 67 marker test, at least for our group, appears to be most useful for sorting out very recent relationships.

Probably, but there is the remote possiblity your family group’s DNA signature “drifted” faster than the average mutation rate, making the computation of your group’s genetic distance inaccurate. You will need to collect DNA signatures from other parts of your family branch to confirm the high mutation rate or you will need solid evidence from traditional sources. Don’t give up, but it’s likely you’re not related within a useful time frame.

Search your other family lines in the same way we’re researching this one – find a male from that line and have him tested. Autosomal testing can help with recent ancestry (within approximately the last four or five generations.)

We really want your contribution and help with the Project. The Project uses Y-DNA and only men have that, but you can contribute to the effort by helping us recruit men into it, e.g. getting your father or an uncle or your brother or cousin to submit a test sample.

You would do this if you wanted to locate the line from which you are genetically descended. If you know the surname of your biological father, then you’d be best served by joining the Project for that surname. If you don’t know, you’re welcome to join the Cloud DNA Project. Once your results are in, they can be uploaded to the Y-Search worldwide database. You’ll find information there on others who share similar signatures as you.

You can tell them this is important to you. Offer to pay for the test for them. Tell them their data will help all of us learn more about our ancestry (it will take many tests from our distant branches to be able to peer back into the distant past). Share with them your copy of the Cloud Family Association Journal and tell them we are earnestly working to learn about and preserve our heritage, and DNA testing can help with that.

A surname is an artificial and arbitrary designation. Your surname is simply an identifier for the family group you identify with. No one even had a surname in the middle ages and before. Someone, somewhere settled on usng this surname – what does it matter whether it was adopted 500 years ago or 50 years ago – it’s still your surname and it is valid. We suspect there are many unrelated families with the surname Cloud. There are records of Clouds coming from many countries of origin. William Cloud left England in 1682 to travel to America, and early census records, ship manifests and even the Ellis Island records show Clouds who immigrated from other countries besides England. There are also Native American people who took the surname Cloud. These are all distinct family groups that aren’t related to each other – but they all are Clouds.

You will purchase an STR test for 67 or 111 markers or, preferably, the Big-Y test from our testing company. You will need to submit whatever information you know about your pedigree to the Project Administrator. When you receive the test kit in the mail, you’ll use the two swabs to collect samples from the inside of your cheek. Then you’ll return the samples to the testing company. Both you and the project administrator will receive your results.

Your DNA test results will be compared with the results of other participants to see if there is a possible match. If there is, your pedigree information will be compared to theirs to find any common factors. That will give you and other researchers clues on where to look to resolve the broken links. Your data will also help us establish a better idea of the DNA signature of our distant paternal ancestor, and we need as much data as we can collect to accomplish that.

We learn more about our connections by comparing both our DNA test results and our pedigree information. The results from a DNA test will place you in a large pool of relatives. You reduce the size of that pool by comparing the markers which differ, but there is no way to know, from the DNA alone, how you are related to those people. A pedigree, even if it is inaccurate, is the next step in putting the pieces together. We use the pedigree information to look for clues to how we’re related – dates, places, given names, surnames of collateral lines, etc. DNA doesn’t solve the puzzle by itself, it just adds a useful piece to it.

Both forms of DNA can be compared to a family crest – in that they are unique to that line. The mtDNA identifies the maternal line and the Y-DNA identifies the paternal line. Mitochondrial DNA is passed by a mother to her children. This makes it useful for tracing the maternal line – a person’s mother, her mother’s mother, her mother’s mother’s mother, and so on. Every person descended from the same ancient female ancestor will carry virtually identical mtDNA. The Y chromosome provides the same benefit. It is carried only by a man and the son receives a virtually identical copy from his father. Every man descended from the same male ancestor will have very similar Y-DNA though it changes more often than does the mtDNA.

The core of the Project is based on Y-DNA because it provides a signature for the paternal line, which is our CLOUD ancestry. Other forms of DNA can also provide useful information to the Project, but they will not be specific to the CLOUD surname and, with the exception of mtDNA, they contain information from all of a person’s ancestors, which makes them difficult to use in a surname project.

The project welcomes input from anyone who has taken a DNA test of any kind, but only the Y-chromosome test can be used in our surname project analysis. That is because the analysis examines Y-DNA markers and the other tests do not return those values. The autosomal and X-chromosome tests return results from all of a person’s ancestors, which introduces so many variables as to make them most useful to closely related people and less useful for distant relatives (e.g. the Project administrator). The Y-DNA test can help trace a surname (paternal) line no matter how distantly related the test subjects may be. (The mtDNA test similarly gives information only on one’s maternal lineage.)

Why would it matter? Don’t they all do the same thing? No. Not all the companies focus on genealogy. Not all companies have good equipment or practice good quality control (i.e. the results they report aren’t consistently accurate). Not all companies test the same markers we use and some don’t adhere to accepted standards of reporting those markers. Not all companies have good customer service. At least one well-known genealogy company refuses to give the DNA results to their customers, which means they can’t compare their results with people who tested elsewhere.

Only Family Tree DNA offers specific tests for mtDNA and Y-chromosome. The other major companies only offer the less-expensive autosomal test (though some include a small sampling of mtDNA and Y-chromosome data to improve their origins estimates). (This is an example of “you get what you pay for”.)

Only Family Tree DNA has group projects offering assistance from project administrators, a valuable resource to the researcher. The projects are typically surname-oriented, though there are also regional projects and haplogroup project.