top-banner

METHODS AND TECHNOLOGIES

Southern Blot Analysis

SOUTHERN BLOT ANALYSIS

This technique is usually used in molecular genetic diagnostics to assess large repeat expansions or contractions, such as those exceeding 110 CTG trinucleotide repeats, and to evaluate DNA methylation status. Genomic DNA is first digested with restriction enzymes that are sensitive to methylation, chosen based on the specific DNA sequence under analysis. The digested fragments are then separated by size through agarose gel electrophoresis and transferred to a nylon membrane as part of the Southern blot process.

The DNA on the membrane is hybridized with a labeled probe, which can be radioactive but is increasingly non-radioactive. In non-radioactive methods, detection involves an indirect process using a fluorescence-labeled antibody after exposure to an X-ray film placed over the membrane. The resulting band patterns on the developed film are analyzed and interpreted.

Southern blot analysis is particularly useful in the molecular genetic examination of triplet repeat disorders, such as myotonic dystrophy type 1, where it allows for the sizing of large repeat expansions (>110 CTG) that cannot be measured through capillary electrophoresis-based fragment length analysis. It is also crucial in investigating conditions like fragile X syndrome, where it helps determine if triplet repeat expansions lead to methylation of the affected region, which, in turn, can inhibit transcription and result in the loss of the FMR1 gene product.

Although time-consuming, this method is a reliable and well-established tool in genetic diagnostics. In some cases, the use of different restriction enzymes and probes is required, but it generally provides only an approximate estimate of repeat numbers. Accurate interpretation of band patterns requires expert knowledge.

WAYS TO PARTNER WITH US

TarCET IVD Kits

CE-IVD kits containing reagents
for hereditary indications in
an easy-to-use kit form

Learn more

Technology Transfer

Out-of-the-box genetics workflow
from sequencing to reporting
for non-invasive prenatal testing

Learn more

Genetic Testing Laboratory

Your partner for
all genetic tests

Learn more

Contact Us

Please get in touch with us
for any questions, inquiries,
feedback, or with any
comments you might have.

Learn more

BLOG ARTICLES

February, designated as Cancer Awareness Month, marks a time to reflect on the remarkable progress made in cancer research and to inspire hope for th…

Read more

Introduction Cardiovascular disease (CVD) is a major health issue as it remains a leading cause of death worldwide [1]. CVD is responsible for mor…

Read more

Antimicrobial resistance (AMR) is one of the most pressing global health threats, and accurate identification and surveillance of multidrug-resistant…

Read more

Colorectal cancer remains a significant health concern globally. While genetic factors play a crucial role in its development, identifying the exact …

Read more

A new meta-analysis links trans-kingdom gut microbiota (bacteria, eukaryotes, viruses, archaea) to immune checkpoint inhibitor (ICI) response in canc…

Read more

Reproductive health is a fundamental aspect of human well-being, affecting individuals and communities worldwide [1]. It encompasses a wide range of …

Read more

It seems as though everyone is talking about artificial intelligence, usually referred to as AI, these days! Indeed, not only are AI tools now access…

Read more

Orphan drugs are those developed specifically for the treatment of rare diseases. Within the pharmaceutical industry, the drug development process is…

Read more

A study of 629 pregnancies with ultrasound-detected anomalies found that exome sequencing identified pathogenic variants in 14% of cases. The detecti…

Read more

Breast cancer is a type of cancer that originates in the breast cells. Genetic changes in the DNA of the healthy breast cells can lead to the formati…

Read more

OUR NETWORK