Human genetics has fascinated scientists since time immemorial.
In recent years, understanding human genetics has led to the development of medications for many previously incurable diseases.
However, there is a particular facet of these studies that we need to consider.
Who participates in genetic studies, and who does not?
Could these biases affect the study results?
And most importantly, are our genes responsible for such a bias?
We answer all these questions here.
What is Genetic Research?
Genetic research analyzes human DNA to identify genes that can cause diseases.
Most health conditions have a genetic component.
They can be either entirely genetic or can be a mix of genetics, lifestyle, and environment.
There are around 25,000 genes that make up the human body.
Genes are made up of DNA.
The DNA has specific codes that determine how a gene works.
When this code is altered, the functioning of a gene changes.
Sometimes, this change can be in a single letter called Single Nucleotide Polymorphism or SNP for short.
Most SNPs don't cause any health issues.
However, the effects of a few or several SNPs put together can contribute to disease risk.
In genetic research studies, scientists aim to find out the exact genetic and environmental contribution to each disease.
Types of Genetic Research
Genetic studies can be of different types.
They can involve small or large groups of people or even individuals.
The following are some types of genetic studies.
Research involving families
This type of genetic study is also known as linkage analysis.
Common diseases like autism, Alzheimer's, and cancer affect many individuals worldwide.
1 out of every 110 children will develop autism, while 1 in 10 and 1 in 3 adults will develop Alzheimer's and cancer, respectively.
Often, these diseases run in families.
More than one individual in the family is usually affected by the disease.
When such families are involved in genetic research, scientists can discover the specific gene mutation responsible for the disease.
The region where this mutation is prevalent can also be more specifically identified.
It will better our understanding of these diseases and can assist in developing treatment options.
Research involving large groups of people
This type of genetic study is called association.
In this study, two groups of people are chosen for DNA testing.
One group usually has a disease, while the other group, called the control, does not
Scientists study the SNPs present in the participants.
Sometimes, one type of SNP is found more frequently in people suffering from certain diseases like Alzheimer's.
This variation can be identified in an association study.
This type of research requires the participation of many people.
Research involving candidate genes:
Candidate genes are located on specific DNA parts associated with certain diseases.
Researchers will examine these genes to determine how they contribute to a disease.
Why Are Some People More Likely To Participate In Genetic Studies?
A groundbreaking study by Oxford’s Leverhulme Center for Demographic Science and Big Data Institute showed that people participating in genetic studies are more genetically likely to do so.
Currently, genetic studies are conducted using genetic databases containing information on a large population.
However, using this data can lead to what is called an ascertainment bias.
Ascertainment bias occurs when some people are more likely to be included in the study than others, resulting in the representation not reflecting the intended study population.
For example, imagine you are conducting a study on school students to find out the favorite hobbies of 6-12-year-olds. You go into the art class and ask the students there. You likely would have gotten answers like painting, drawing, etc. If you conclude that the favorite hobby of your target population is painting, your answer is clouded by ascertainment bias since those with painting as a hobby are overrepresented in your study population.
The Study
The researchers used the UK Biobank, one of the world's largest biomedical databases, to study the connection between genetics and participation bias in genetic studies.
They found that some people have certain gene changes that make them more likely to join these studies.
Professor Kong says this could lead to ascertainment bias since sometimes, only certain types of people join, which can make the study's results a bit off.
Therefore, the genetic data collected from studies might not represent the intended study population.
Genetic research is based on extensive data collection from many people.
However, if only some people participate and others don't, it can lead to inaccurate results.
The study further reported that the genetic trait influencing participation has a 36.6% correlation with the genetic factors underlying educational attainment.
This means there's a link, but participation isn't merely a result of traits like education or body mass index.
The genetic inclination to participate in studies can be inherited, potentially impacting individuals' participation in various studies throughout their lives.
This discovery underscores the need to consider such biases when designing and analyzing genetic research.
What Effect Does This Have On Genetic Studies?
Genetic studies offer essential insight into the relationship between genetics and human health.
They help scientists understand how particular genes or specific mutations can cause diseases.
These studies are vital for developing effective medications against some commonly occurring diseases.
However, participation bias can affect the study results.
If only some people participate, the results might not represent the intended study population.
Surprisingly, these biases can run in families.
They can affect people's participation in different studies over their lifetime.
Thus, accounting for this bias is necessary for accurate results from genetic studies.
By accounting for these biases, the results of genetic studies might be complete.
Summary: Participation In Genetic Studies
Common diseases like cancer and Alzheimer's run in families.
They are caused by a genetic mutation that can be passed down through generations.
It is where genetic research steps in.
These studies help identify the gene mutations that cause these diseases.
Understanding the nature of these diseases can help develop treatments and medications.
However, a new study has shown that only some people participate in genetic studies.
Genes determine if a person will ever participate in genetic studies in their lifetime.
This phenomenon can give rise to participation bias.
This means the data collected will not represent the intended population and will show inaccurate results.
Understanding who participates in genetic research will help scientists consider such biases.
