How to Interpret Your Raw DNA Data Easily and Unlock Your Ancestry

How to Interpret Your Raw DNA Data Easily and Unlock Your Ancestry

You’ve just received your DNA test results: a massive spreadsheet filled with countless rows of genetic code. Excited yet overwhelmed, you wonder: Is this really the key to understanding your genetic makeup?

Scrolling through the endless columns of data, frustration sets in. What do all these strange numbers and letters mean? Which genetic variations actually matter? How do they impact your health, traits, and ancestry? Without proper interpretation, your genetic data is just a sea of meaningless symbols.

Whether you’re aiming to improve your health, understand your traits, or explore your ancestry more deeply, this guide will help you unlock the full potential of your genetic information. Let’s turn those mysterious genetic symbols into actionable insights that can inform your life decisions.

» Get the most out of your raw genetic data by taking a DNA test

What is raw DNA data?

Your DNA holds a vast amount of information about you, but raw DNA data itself isn’t readily understandable. It’s like a long code made of letters (A, T, C, G) representing the building blocks of your genes. While most people’s DNA is very similar, those tiny variations — single nucleotide polymorphisms (SNPs) — make you unique.

This raw data needs analysis to unlock its secrets. For example, MyHeritage uses it to create reports with insights into your family history. Think of raw data as a coded message. It might look like gibberish, but experts and specialized tools can decipher it. This data usually comes in simple text files (.txt or .csv) that you can open with basic programs like Notepad or Excel.

» Learn how your father’s genes affect you by understanding Y-DNA tests

Why raw DNA data matters

While summarized reports offer a good starting point, they can be limited. Here’s where raw data shines:

  1. Uncovering hidden ancestry: Platforms like MyHeritage help you explore connections beyond what standard reports offer. By analyzing raw data, you can compare your DNA to a wider pool of samples, potentially finding distant relatives.
  2. Deeper dives: Raw data gives you the freedom to delve deeper into your genetic information. Summaries provide a simplified overview, but raw data helps you explore specific traits or ancestry regions.
  3. Future-proofing your DNA: As DNA science advances, raw data ensures you’re ready for new discoveries. You can apply new analysis techniques to your existing data, without needing another test.

» Get the low-down on genetic markers before you interpret raw DNA data

How to interpret your raw DNA data

Step 1: Obtain your raw DNA data

To begin, you need to choose a genetic testing service that suits your needs, such as MyHeritage. Once you select a service, you’ll submit a sample, which involves collecting saliva in a provided kit and sending it back to us.

After we process your sample, you’ll recieve an email notification that your results are ready. Log into your account on the service’s website, navigate to the section for raw data, and look for the option to download your raw DNA data. This information often comes in a .zip file format.

Step 2: Prepare the data for analysis

After downloading the .zip file containing your raw DNA data, the next step is to unzip this file on your computer. You will find a text file (commonly in .txt format) that contains your raw DNA information.

Open this text file using a text editor such as Notepad or a spreadsheet application like Microsoft Excel. If you choose Excel, make sure to select the option to open it as a tab-delimited file so you can improve readability. This way, you can to view the data in columns, which makes it easier to analyze.

» Determine how you’re related with someone with Shared DNA Matches

Step 3: Analyze specific gene variants

Once you understand the structure of your data, you can begin analyzing specific gene variants. Start by checking relevant SNPs that correspond to health conditions or traits you are interested in exploring. You can use online databases such as dbSNP or Ensembl to look up specific rsIDs and find information about their associations with various traits and diseases. [1,2]

You should also consider using third-party tools that allow you to upload your raw DNA data for further analysis. MyHeritage can generate reports summarizing potential health risks, traits, and ancestry information based on your genetic markers.

Step 4: Perform quality control (if applicable)

If you are working with high-throughput sequencing data rather than just genotyping results, performing quality control is essential. Start by assessing the quality of your sequencing reads using tools like FastQC. This software provides visualizations and metrics that help identify low-quality sequences or other issues in your dataset.

If they detect any, you should use trimming tools such as Trimmomatic or Cutadapt. They help you remove low-quality bases and adapter sequences from your data before doing more analysis.

» Find out how DNA looks under a microscope

Step 5: Align reads and identify variants (for sequencing data)

Aligning reads against a reference genome is crucial for accurate variant identification. You can use tools like BWA (Burrows-Wheeler Aligner) to map your reads onto a reference genome. This step ensures that you correctly place each read according to its corresponding location on the genome.

After alignment, proceed with variant calling using software such as SAMtools or VarScan. They analyze aligned reads to detect SNPs and indels (insertions/deletions) within your dataset. The output will provide a list of identified variants that you can explore further.

» Develop your first DNA testing plan

Aligned reads against a reference genome.

A graph of aligned reads against a reference genome.

Step 6: Interpret results

Finally, it’s time to interpret your results. If you have used third-party services for analysis, carefully review the generated reports that summarize potential health risks, traits, and ancestry information based on your genetic markers. You should also pay attention to any significant findings related to health conditions or traits of interest.

If you discover notable health-related information or variants that may have implications for your health or lifestyle choices, consider consulting with a genetic counselor or healthcare professional who specializes in genetics. They can provide personalized guidance based on your results and help you understand any potential implications for your health and well-being.

» Get the most out of your DNA test

4 limitations of raw DNA data analysis

1. Inaccuracies in raw data

Raw DNA data from tests may contain errors. A study revealed that around 40% of genetic variants in raw DNA data were false positives when clinically confirmed. [3] To ensure accuracy, validate raw genetic data with clinical-grade testing before making health-related decisions. Seek guidance from genetic counselors or healthcare professionals for accurate interpretation and context of the results.

2. Issues with reference groups

The accuracy of genetic interpretations rests on the quality and diversity of reference groups used in analysis. Many companies use reference populations that may not adequately represent the genetic diversity of all people, especially those from underrepresented ethnic backgrounds.

For example, ancestry tests often provide vague results for minority populations due to limited representation in reference datasets, resulting in misleading ancestry estimates and health risk assessments.

In forensic DNA mixture analysis, the accuracy of likelihood ratio (LR) calculations is significantly impacted when the reference allele frequencies are mis-specified. For groups with lower genetic diversity, false inclusion rates can be particularly high, leading to wrongful convictions in criminal cases.

To address this issue, separate LR calculations should be done using multiple reference allele frequency distributions and the results should be combined carefully. Implementing a more selective approach in DNA mixture analysis, such as limiting analyses to mixtures with fewer contributors, can also help reduce false positives.

» Find out more about genetic groups

3. Analytical limitations

Testing companies like MyHeritage often use sequencing methods that only examine a small portion of your DNA. This can lead to errors in the raw data, which may result in incorrect SNP calls. These mistakes can impact downstream analyses, such as variant classification and health risk predictions. Additionally, the algorithms used to interpret this data may struggle to accurately distinguish between closely related ancestries.

When we compare DNA sequencing data to a single reference genome, genetic differences between the reference and the sample can lead to mistakes in identifying genetic variation.

To address this limitation, you can use de novo assembly techniques. This approach constructs a new reference genome directly from the sequenced data, which can lead to more accurate results. But, it requires higher coverage and longer reads. Plus, using multiple reference genomes for mapping can help identify discrepancies and improve overall data quality.

4. Psychological impact

Receiving inaccurate genetic information can have serious emotional consequences. Some people have been falsely told they are at risk for serious health conditions. This can cause significant distress and anxiety. To minimize this harm, you should consult with professionals both before and after genetic testing. They can help manage expectations and guide your through the raw DNA analysis.

» Understand how much DNA you share with relatives

Time-consuming task of manual DNA analysis

It can take anywhere from hours to several weeks to manually interpret raw DNA data. This process requires identifying the important SNPs, finding the key markers, and comparing the DNA sample against the reference groups.

There is a steep learning curve to understanding the data, and you have to know what you are looking for when conducting your research. The more knowledgeable you are about how DNA works, the less time–everything else is likely to take. They say knowledge is power, but in this case, it’s also worth its weight in time.

The complexity of accessing the information you are seeking, mitigated by the tools available for your use, will also greatly influence the time it takes to complete the research. How many reference groups are you comparing with your sample, and what is the size of those datasets?

Just because you are doing your research manually doesn’t mean you have to forgo the use of all tools and resources. You should selectively use them to reduce your research time considerably.

» Trying to find you birth parents? Get help from DNA angels

Use Your raw DNA data for ancestry insights

When you upload your RAW DNA data to MyHeritage, we analyze it by focusing on approximately 700,000 SNPs. Then, we perform several critical steps to get your results.

They are:

  • Extraction and amplification: The DNA is extracted from your sample and amplified to create sufficient quantities for analysis.
  • Genotyping: This process determines the specific nucleotides (A, T, G, C) at each SNP location in your DNA.
  • Phasing and imputation: Phasing separates the genetic variants inherited from each parent, while imputation infers missing SNPs based on known data, allowing for more comprehensive comparisons with other users’ data

You’ll get an Ethnicity Estimate that breaks down your genetic ancestry into percentages representing various ethnic groups. This estimate is generated by comparing your SNP data against models of different populations, allowing you to see where your ancestors may have originated. You can then view detailed results through the Ethnicity Estimate tab, which includes a map of ancestral birth locations if linked to your family tree.

MyHeritage also finds your potential relatives by comparing your DNA segments with those of other users. When we find significant matches — indicating shared segments of DNA — it suggests a common ancestor. You can also filter these matches based on relationships (e.g., close family vs. distant relatives), ethnicity, and shared surnames.

If you want an even deeper analysis, MyHeritage offers several tools:

Unlocking your genetic story: The path forward

Understanding your raw DNA data is like learning a new language—challenging at first, but immensely rewarding once mastered. While the journey through your genetic code may seem daunting, remember that every person who has successfully interpreted their DNA data started exactly where you are now.

The power to understand your genetic information is no longer locked away in research laboratories or restricted to genetic counselors. With the right tools, knowledge, and cautious approach outlined in this guide, you can responsibly explore the wealth of information hidden in your genes.

Remember that your genes are just one part of your story. They provide insights, not destiny. Use this knowledge as a tool for informed decision-making, not as an absolute predictor of your future.

Your DNA is unique to you—and now you have the keys to unlock its secrets.

» Understand what makes you unique by taking a DNA test