This post is part of a miniseries on genetics. Be sure to check out the other posts in this series that you may have missed.
Credit: NIGMS.
In our miniseries on genetics, we’ve introduced the genome and how variants in DNA affect us. We’ve also discussed how people inherit genetic information and the way genes are expressed, as well as common tools researchers use to study DNA. We hope you’ve paid close attention because it’s time to test your knowledge of genetics! Take our quiz below, and let us know how many questions you answered correctly.
This post is part of a miniseries on genetics. Be sure to check out the other posts in this series that you may have missed.
DNA carries information needed for all cellular functions. Credit: NIGMS.
You may wonder how scientists study something as tiny as DNA. Over the past decades, researchers have developed a wide range of tools and techniques to help them unlock the secrets of human genomes and those of other organisms. Two key examples are DNA sequencing and gene editing.
DNA Sequencing
DNA sequencing, sometimes called gene or genome sequencing, enables researchers to “read” the order of the bases in a segment of DNA, which contains the information a cell needs to make important molecules like proteins, the functional building blocks of the cell. There are several methods for sequencing, but they all require many copies of the same DNA segment to get accurate results. Fortunately, scientists have developed a technique called polymerase chain reaction, often referred to as PCR, that can quickly and inexpensively create a large number of copies of a DNA segment.
This post is part of a miniseries on genetics. Be sure to check out the other posts in this series that you may have missed.
Have you ever been told that you have your mother’s eyes? Or maybe you’ve found that you and your father share a condition such as asthma? People who are biologically related often have similarities in appearance and health because they have some of the same geneticvariants. However, you’ve likely noticed that siblings with the same biological parents can differ significantly. Each person’s genome is a combination of DNA from both of their parents, but siblings’ DNA can differ because of the mixing and matching involved in creating reproductive cells.
If you like this post, check out our other “By the Numbers” posts!
Even though scientists have been studying genetics since the mid-19th century, they continue to make new discoveries about genes and how they impact our health on a regular basis. NIGMS researchers study how genes are expressed and regulated, how gene variants with different “spellings” of their genetic code affect health, and much more. Get the drop on DNA and the gist of genes with these fast facts:
Genetics is the study of genes and heredity—how traits are passed from parents to children through DNA. A gene is a segment of DNA that contains instructions for building one or more molecules that help the body work. Researchers estimate that humans have about 20,000 genes, which account for about 1 percent of our DNA. The remainder of the DNA plays a role in regulating genes, and scientists are researching other potential functions.
Pharmacology is the study of how molecules, such as medicines, interact with the body. Scientists who study pharmacology are called pharmacologists, and they explore the chemical properties, biological effects, and therapeutic uses of medicines and other molecules. Their work can be broken down into two main areas:
Pharmacokinetics is the study of how the body acts on a medicine, including its processes of absorption, distribution, metabolism, and excretion (ADME).
Pharmacodynamics is the study of how a medicine acts in the body—both on its intended target and throughout all the organs and tissues in the body.
Vials of samples from the NIGMS HGCR. Credit: Coriell Institute for Medical Research.
The year 2022 marked 50 years since the creation of the NIGMS Human Genetic Cell Repository (HGCR) at the Coriell Institute for Medical Research in Camden, New Jersey. The NIGMS HGCR consists of cell lines and DNA samples with a focus on those from people with rare, heritable diseases. “Many rare diseases now have treatments because of the samples in the NIGMS HGCR,” says Nahid Turan, Ph.D., Coriell’s chief biobanking officer and co-principal investigator of the NIGMS HGCR. She gives the example of a rare disease advocacy group who worked with the NIGMS HGCR to establish a cell line several decades ago. It was used to identify a gene associated with the disease, which aided in the development of five treatments that have received approval from the Food and Drug Administration.
Researchers have also studied NIGMS HGCR’s samples to help advance knowledge of basic biology and genetics, and even to support the development of a vaccine for a deadly virus.
American Indian and Alaska Native (AI/AN) populations have long experienced health disparities such as higher rates of diabetes, certain cancers, and mental health conditions than those of other Americans. One contributing factor in these disparities is underrepresentation of AI/AN populations in biomedical science—as study participants, researchers, and health professionals. Unfamiliarity with health care options and opportunities, coupled with a distrust of biomedical research resulting from unethical studies in the past, have exacerbated this underrepresentation.
NIGMS-supported researchers, including Native scientists, are partnering with AI/AN Tribes to help reduce health disparities by conducting research focused on AI/AN health priorities and building infrastructure that supports research in those communities. They’re also preparing Native students to pursue careers in science and medicine. In this post, you’ll meet four scientists advancing AI/AN health.
“DNA is an amazingly beautiful molecule, and it’s so important. Each of our cells has only one copy of DNA, and if it gets damaged, that messes up everything else in the cell,” says Alexis Komor, Ph.D., an assistant professor of chemistry and biochemistry at the University of California, San Diego (UCSD). Check out the highlights of our interview with Dr. Komor to learn about her scientific journey, research on DNA, and advice for students.
Q: How did you decide to study chemistry?
A: I really enjoyed math and science in middle and high school. When I applied to college, I knew I wanted to major in science over math because I felt like it was more relevant to what we experience on a day-to-day basis. I ultimately went into chemistry for a silly reason, but looking back now, I’m so very grateful that I did. Chemistry has this nice balance because it allows you to not only understand how things work on a molecular level but also see how those molecular workings relate to everyday phenomena—for example, understanding how DNA damage on a molecular level can lead to negative health outcomes.
Over the past 2 years, you’ve probably heard a lot about the spread of SARS-CoV-2—the virus that causes COVID-19—and the emergence of variants. The discovery and tracking of these variants is possible thanks to genomic surveillance, a technique that involves sequencing and analyzing the genomes of SARS-CoV-2 virus particles from many COVID-19 patients. Genomic surveillance has not only shed light on how SARS-CoV-2 has evolved and spread, but it has also helped public health officials decide when to introduce measures to help protect people.
In December 2021, the NIGMS-supported SARS-CoV-2 genomic surveillance program at the University of New Mexico Health Science Center (UNM HSC) in Albuquerque detected the first known case of the Omicron variant in the state, which enabled a rapid public health response. The program’s co-leaders, assistant professors Darrell Dinwiddie, Ph.D., and Daryl Domman, Ph.D., were watching on high alert for it to enter New Mexico, and when it did, they were poised to quickly identify it:
