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Online genetic testing takes 6-8 weeks

Why Does Health and Ancestry DNA Testing Take So Long?

After you mail back your sample, it takes quite some time before you get an email telling you the results are ready.

FTDNA, 23andMe, AncestryDNA and other online genetic testing services all provide an estimate turnaround time of 6-8 weeks.

They are also careful to note that this is just an estimate. Your results could take even longer if the volume of tests goes up or your sample needs to be re-tested.

For certain more complex tests, the turnaround time is usually longer.

For instance, FTDNA’s 500-marker Big Y ancestry test currently has a turnaround time of 10-12 weeks. That’s roughly 3 months of waiting for your test results.

Why the heck do these tests take so long?

There are a few reasons which I explain below.

Analyzing DNA Takes Time

Your DNA is scattered around 20,000-25,000 genes located in 23 pairs of chromosomes which are housed in each of the trillions of cells in your body.

DNA – the genetic information that makes you who you are – is coded using nucleotides. There are 3 billion pairs of nucleotides in your entire genome.

When your sample gets to the lab, the technicians get to work extracting the DNA from the cheek swab.

They then prepare the extracted DNA for analysis by amplifying it (copying it many times over).

To analyze the DNA, they look at SNPs (‘snips’) or single nucleotide polymorphisms. These are the markers or variations in your DNA sequence that differentiate you from other individuals.

The human genome has about 10 million SNPs spread at various points along the DNA. But DNA testing companies don’t look at all of them. They don’t have the resources or time to.

Instead, they use genotyping or microarray chips. This is a glass slide that is already ‘pre-programmed’ with known genetic variants or SNPs.

The Chip allows the lab technicians to find similar variants in your DNA.

Reading your DNA with a genotyping chip is cheaper, faster and more practical. Trust me, it could be worse.

The alternative is sequencing. This is where researchers determine the exact nucleotide sequence of various parts of DNA.

It was the method used by scientists in the Human Genome Project. It took them 15 years to finish sequencing the DNA from a just few samples.

To be fair, they sequenced the entire human genome (99% to be specific) while these companies only analyze a small portion of it.

But it would still be very expensive and time-consuming to use gene sequencing.

Comparing Your DNA

DNA is a vast and complicated structure

The process doesn’t end when they find the SNPs they are looking for.

In the case of 23andMe’s health report, they’ll check which diseases you are at risk of based on the genetic variants they’ve found.

For ancestry reports, there’s even more work to be done. They have to compare your SNPs against those of other DNA samples in their database.

This is how they determine your ethnicity makeup and find possible matches who might be your family members.

These databases typically have over a million samples. AncestryDNA’s database is currently over 10 million strong.

So even though most of this analysis is done by a computer, it still takes time.

Shipping Time and Volume

Another reason why your genetic test takes so long is that these companies typically tests thousands of samples every month.

They are all tested at just one or two labs.

Each sample has to go through the same extensive preparation and analysis process.

And even if you happen to send in your sample during a low-volume week, you have to account for extra time taken to ship the sample collection kit to you and for you to send it back.

This can easily add a week or two to the overall turnaround time.

Can I Get an Expedited Test?

Many companies including 23andMe and FTDNA offer expedited shipping for sample collection kits (at an extra fee). But the results will take as long as they have to.

They don’t expedite tests.

Check your account for the estimated turnaround time. It will usually be indicated. And if you think your results are taking too long, you can always contact customer support.

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About the Author Charles McKnight

I'm just another amateur genealogist investigating my American-Scots-Irish lineage. I built MyFamilyDNATest.com after buying all of the leading DNA tests to discover everything I could about my family history. Hopefully, this site will save you time and demystify the emerging science of DNA-based genealogy, for your family project.

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