What Is a Buccal Cell and What Is It Used For?

Buccal cells, sourced from the inner lining of the cheek, are a tool in modern science and medicine. These readily accessible cells provide a window into an individual’s genetic makeup, offering information for many applications. Their ease of collection has made them a common choice for researchers and clinicians who require biological samples for analysis. This has led to their widespread use in fields from genetic testing to large-scale epidemiological studies.

Defining Buccal Cells

Buccal cells are a type of epithelial cell, specifically classified as squamous epithelial cells. They form the protective lining of the buccal mucosa, the tissue on the inside of the mouth. These cells are characterized by a flat, irregular shape and contain a prominent nucleus, which houses an individual’s complete set of DNA. The tissue that lines the mouth is in a constant state of renewal. As a result, older cells are continuously shed from the surface of the mucosa, making them easily collectible for analysis.

Buccal Cell Collection Techniques

One of the most common methods involves using a buccal swab, which may be a cytobrush or a sterile applicator with a cotton or foam tip. The collector gently but firmly rubs the swab against the inside of a person’s cheek for about 10 to 15 seconds on each side to dislodge and capture the epithelial cells.

An alternative technique is the oral rinse or mouthwash method. In this procedure, an individual swishes a sterile saline solution or water in their mouth for up to 60 seconds and then expels the liquid into a collection tube. For optimal sample quality, individuals are often asked to refrain from eating, drinking, or smoking for at least 30 minutes prior to collection to minimize contamination.

Key Uses of Buccal Cells

The most prevalent application for buccal cells is DNA analysis, as each cell contains a person’s entire genetic blueprint. Genetic testing companies frequently use these cells for ancestry tracing and paternity tests. In a medical context, the extracted DNA can be screened for genetic markers associated with predispositions to certain diseases, allowing for early intervention or monitoring.

In the field of forensic science, buccal cells are routinely used to create DNA profiles of individuals. Law enforcement agencies collect reference samples from suspects or victims to compare against DNA evidence found at a crime scene. A match between the DNA from a buccal sample and crime scene evidence can help link a suspect to the scene or exonerate them.

These cells are also used in diverse areas of scientific research. Epidemiologists use them in large-scale studies to investigate disease patterns across populations, as the ease of collection facilitates high participation rates. Pharmacogenomics researchers study DNA from buccal cells to understand how an individual’s genetic makeup affects their response to specific drugs.

Factors in Buccal Cell Sampling

One of the main reasons buccal cells are frequently chosen is the non-invasive and cost-effective nature of the collection process. Unlike blood draws, which require a trained professional and can cause discomfort, collecting a cheek swab is simple enough for individuals to do themselves with a home kit. This convenience makes buccal cells suitable for studies involving children, elderly participants, or large, geographically dispersed groups.

However, there are some limitations to consider. The quantity of DNA obtained from buccal swabs is lower than that from a blood sample, which can be a factor for certain analyses. Samples are also susceptible to contamination from bacteria present in the oral cavity, which can interfere with molecular assays. Proper handling and storage, such as air-drying swabs and freezing samples, are important to maintain the integrity of the genetic material.