1985 Nobel Prize in Physiology or Medicine — Brown and Goldstein, Discovering the LDL Receptor and the Gatekeeper of Cholesterol Metabolism

What You'll Learn in This Article

You'll understand the story of two individuals who elucidated the genetic basis for why some people have high blood cholesterol levels and others have low levels. Michael Brown and Joseph Goldstein delved into the cells of individuals with familial hypercholesterolemia at the University of Texas Southwestern Medical Center and revealed that the dysfunction of a gatekeeper protein called the LDL receptor is the cause. We'll also explore how this discovery led to today's statin drugs, PCSK9 inhibitors, and standard cardiovascular prevention treatments, and how these two colleagues, only a year apart in age, collaborated on research for 25 years in a way that made sharing their accomplishments impossible.

A Story Different from Common Knowledge — People Who Get Sick Because Cholesterol Doesn't Enter

When we talk about cholesterol, we often think of it as something bad that we should avoid. Egg yolks, pork belly, butter — the common wisdom is that reducing foods high in cholesterol is good for your health. In reality, cholesterol is an essential component for building cell membranes and synthesizing steroid hormones, but excessively high concentrations in the blood can be a risk factor for atherosclerosis and cardiovascular disease.

Here is a case that flips the common understanding. Individuals with familial hypercholesterolemia, a genetic disorder. It is a relatively common genetic disorder, affecting about 1 in 500 people. These individuals have several times the normal amount of cholesterol in their blood. And they have a very high probability of dying from a heart attack before the age of 45, and in severe cases, even before the age of 20.

However, even when these patients are put on a low-cholesterol diet, they don't get much better. The problem is not the cholesterol they eat, but the fact that the cells in their bodies cannot absorb cholesterol. Cholesterol is circulating in the blood, but the cells don't absorb it, so it continues to accumulate in the blood and builds up in the blood vessel walls, leading to atherosclerosis.

What Brown and Goldstein revealed was that the cause is a dysfunction of a cell surface protein called the LDL receptor. LDL (low-density lipoprotein) is like a truck that carries cholesterol. The cell membrane must have a receptor (docking station) to receive this truck, but in the cell membranes of patients with the genetic disorder, this receptor is defective or insufficient. As a result, the truck cannot dock and continues to float in the blood, eventually accumulating in the blood vessel walls.

In the language of computer science, this is a code bug in the cell membrane API endpoint. The LDL receptor is a cell's API endpoint for receiving specific cargo (cholesterol) from the outside. If the gene defining this endpoint has a mutation, the endpoint will be deployed in a failed state. As a result, the client (LDL) cannot send data, and requests pile up in the client queue (blood). The system is overloaded, and residue accumulates in the downstream pipeline (blood vessels).

The power of this perspective lies in the clarification of the treatment strategy. If the endpoint cannot be fixed, then the upstream source must be blocked — by inhibiting the cholesterol synthesis pathway in the liver to reduce the production of cholesterol itself. This is the basis for statin drugs. It's a middleware intercept that inhibits HMG-CoA reductase, which reduces cholesterol synthesis itself. The 1985 Nobel Prize discovery led to the FDA approval of lovastatin in 1987, and statins have become one of the most prescribed drugs in the world for the past 30 years.

The Landscape of the Time — The Beginning of the Thaw in the Cold War and the Popularization of GUI

1985 was the year that the geography of the Cold War began to shift decisively.

The biggest tectonic shift in world history was the inauguration of Mikhail Gorbachev as General Secretary of the Communist Party of the Soviet Union on March 11. The relatively young leader, at 54, took control of the Soviet Union and subsequently promoted two key policies: Perestroika (reform) and Glasnost (openness). This marked the beginning of the trajectory that would lead to the dissolution of the Soviet Union five years later. In May, a paper was published announcing the discovery of the ozone hole over the Antarctic — a clear confirmation of the impact of human activity on the Earth's system. This led to the Montreal Protocol in 1987 and the beginning of international environmental cooperation.

On July 13, Live Aid was held simultaneously at Wembley Stadium in London and JFK Stadium in Philadelphia, and broadcast via satellite to 1.5 billion people worldwide. This charity concert for Ethiopian famine relief became one of the most iconic events in pop music history. On November 20, Microsoft Windows 1.0 was released — a GUI shell that runs on DOS, marking the beginning of a 30-year transformation of personal computing. In April, the failure of the New Coke launch and the revival of Classic Coke in July became a classic case of consumer resistance, cementing its place in marketing textbooks. In July, Back to the Future was released and became a cultural icon.

In South Korea, in September, the Kim Geun-tae torture incident at the Namsan Detention Center occurred — 22 days of waterboarding and electrocution by Lee Geun-an and others. Kim Geun-tae's testimony and revelations became a pivotal moment in the Korean democratization movement. Incidents at Seoul National University, such as the suicide of a female student council president and the ideological book incident, continued on campus. In professional baseball, the Haitai Tigers began their three-year championship streak.

In this turbulent year, the Nobel Committee recognized the two individuals who had elucidated the genetic basis of cardiovascular prevention. As the balance of international politics shifted, the genetic mechanism of cardiovascular disease, the leading cause of death worldwide, was revealed.

Brown and Goldstein — The 25-Year Journey of Two Colleagues One Year Apart in Age

Michael S. Brown (1941~) is an American physician. He received his Ph.D. in Medicine from the University of Pennsylvania in 1966, was a researcher at the National Institutes of Health (NIH) from 1968 to 1971, and has been a professor at the University of Texas Southwestern Medical Center since 1976.

Joseph L. Goldstein (1940~) is an American physician. He received his Ph.D. in Medicine from the Southwestern Medical School in 1966, was a researcher at the NIH from 1968 to 1970, and has been a professor at the Southwestern Medical Center since 1977 — almost the same trajectory as Brown. Goldstein was born into an ordinary family who owned a clothing store, and was not particularly outstanding, but his story of winning the Nobel Prize is interesting.

The two met as colleagues, one year apart in age, and followed the same path from the NIH to the Southwestern. In a later reflection after winning the Nobel Prize, they said that they truly collaborated on all of their research to the extent that sharing their accomplishments was impossible. A 25-year collaboration. Goldstein's reflection that there is nothing more powerful in life than having a reliable colleague is well-known.

Goldstein himself summarized several conditions that led to him receiving the Nobel Prize.

First, the appropriateness of the research topic: After discovering that some atherosclerosis and heart disease are genetic in a large-scale epidemiological study by the Seattle Human Genetics Research Institute, he became interested in the cause.

Second, the appropriateness of the research method: Tissue culture was essential for the discovery of the LDL receptor. Goldstein learned tissue culture techniques from Nirenberg (Nobel Prize winner in 1968) at the NIH. Without this technique, the discovery would have been impossible.

Third, the appropriateness of the research subject: Through the Genetic Disorders Research Center affiliated with the Southwestern Medical School, cells from patients with familial hypercholesterolemia and their families could be easily obtained.

Fourth, setting the right hypothesis (although it was initially wrong): Initially, they assumed that there was an abnormality in the cholesterol synthesis enzyme. The experimental results showed that there was no difference between normal and hypercholesterolemic patients — the first hypothesis failed. However, this failure led to the next hypothesis: if it was not the enzyme, then there must be an abnormality in the process of absorbing cholesterol from the blood into the cells.

Fifth, a compatible colleague: As mentioned earlier, the 25-year collaboration between Brown and Goldstein.

The Decisive Experiment — The Striking Contrast in Cultured Skin Cells

The practical problem Brown and Goldstein faced was this: cholesterol is mainly produced in the liver, so they needed liver tissue from patients. However, there was no way to use the liver from living patients as experimental material.

The two chose to culture skin cells and use them for experiments. The tissue culture techniques they learned from Nirenberg proved to be crucial. They cultured skin cells from normal individuals and patients with hypercholesterolemia and compared how LDL was absorbed into the two cell types.

The results were striking. LDL enters normal cells, but it cannot enter the cells of patients. After investigating the cause, they confirmed that the LDL receptor is present on the cell membrane of normal cells, but the receptor is defective on the cell membrane of patients. This receptor is a protein composed of approximately 840 amino acids, and if there is a gene mutation, it cannot bind to LDL.

The impact of this discovery was immediate. The first clear picture of how atherosclerosis, heart disease, and stroke can be understood as genetic disorders. And it opened the way for new strategies for cholesterol control treatment.

CS Framework — API Endpoints and Middleware Intercepts

This discovery can be reconstructed in the language of computer science as follows.

Cell Membrane API Endpoint: Cells communicate with the external environment through various API endpoints. The LDL receptor is one of them — a specific endpoint for receiving cholesterol cargo. This endpoint is defined by the gene code (DNA) and translated into mRNA, which is then deployed to the cell membrane.

Endpoint Code Bug: Familial hypercholesterolemia is a mutation in the LDL receptor gene — that is, a bug in the endpoint code. This bug manifests in several forms:

• Type 1: The receptor is not produced at all (endpoint deployment failure).
• Type 2: Failure to move to the cell membrane (deployment succeeded, but routing failed).
• Type 3: Failure to bind to LDL (mismatch in the docking interface specification).
• Type 4: Failure to be absorbed into the cell after binding (request received, but processing failed).
• Type 5: Failure to recycle (failure to clean up resources after request processing).

Client Queue Overflow: If the endpoint fails, the LDL cargo continues to accumulate in the blood, which is the client queue, and the residue accumulates in the downstream pipeline (blood vessels) — this is the mechanism of atherosclerosis.

Middleware Intercept = Statins: If the endpoint cannot be fixed, there is a way to block the upstream source. Cholesterol is synthesized in the liver from acetyl-CoA, and there is a bottleneck enzyme called HMG-CoA reductase in the early stages of this pathway. Statins inhibit this enzyme, thereby reducing cholesterol synthesis itself. Interestingly, when cholesterol levels in the cell decrease, the cell increases the expression of LDL receptors in an attempt to absorb more LDL from the blood. As a result, blood LDL cholesterol levels decrease.

Precise Refactoring = PCSK9 Inhibitors: PCSK9 is an enzyme that degrades LDL receptors. Administering antibodies that inhibit this enzyme (evolocumab, alirocumab) increases the retention of LDL receptors, thereby increasing LDL absorption. This is an application of hybridoma technology (1984 Nobel Prize) and a precise follow-up refactoring of the 1985 discovery.

This analogy is not perfect. Cells have various feedback regulations, and cholesterol metabolism has complex regulatory circuits involving transcription factors such as SREBP. However, the endpoint-resource-pipeline-middleware architecture perspective is powerful.

Academic Impact: The Statin Era and the Standard for Cardiovascular Prevention

This discovery fundamentally changed the landscape of cardiovascular preventive medicine.

1987: Lovastatin (Mevacor) FDA Approval — The emergence of the first statin drug. Subsequently, simvastatin (1988), pravastatin (1991), atorvastatin (1996, Lipitor), and rosuvastatin (2003, Crestor) were approved sequentially. Lipitor was the world's best-selling drug from 2003 to 2007 and remains the standard for cardiovascular prevention today.

Confirmation through Large-Scale Clinical Trials: Several large-scale clinical trials, including the 4S trial (1994), WOSCOPS (1995), CARE (1996), HPS (2002), and JUPITER (2008), confirmed the efficacy of statins in preventing myocardial infarction and stroke. They were found to reduce the risk of cardiovascular events by 25-35%.

The Era of PCSK9 Inhibitors (2015~): For patients whose conditions are not adequately controlled by statins alone, PCSK9 inhibitor antibodies (Repatha and Praluent) were approved. More recently, inclisiran, a siRNA-based drug, was also approved, inhibiting PCSK9 by silencing mRNA.

Revision of LDL Cholesterol Target Values: The guidelines of the American Heart Association (AHA) and the American College of Cardiology (ACC) have been revised several times, and the target LDL values for high-risk groups continue to decrease – for very high-risk groups, the target is below 55 mg/dL. This reflects the principle of "lower is better."

Attempts at Gene Therapy: In the 2020s, clinical trials are underway using CRISPR gene editing for familial hypercholesterolemia. VERVE Therapeutics, among others, is targeting PCSK9 or ANGPTL3.

The Legacy in Korea Today

The impact of this legacy is also clearly evident in Korea. From the 1990s, statin prescriptions have become standardized at Seoul National University Hospital, Yonsei University Hospital, Seoul Asan Medical Center, and Samsung Medical Center. Today, statins are among the most commonly prescribed drugs for cardiovascular prevention in Korean adults. Atorvastatin (Lipitor) and rosuvastatin (Crestor) are the most frequently prescribed.

Research on the relationship between Korean genetic types and statin response is also actively ongoing. Research teams at Seoul National University Hospital, Asan Medical Center, and Samsung Medical Center have elucidated the relationship between polymorphisms in genes related to statin metabolism, such as SLCO1B1, and the risk of myalgia. This is the foundation for personalized statin prescriptions.

The diagnosis and treatment of familial hypercholesterolemia have also been standardized in Korea. At Seoul National University Hospital and Samsung Medical Center, genetic testing and early statin prescriptions are used to prevent myocardial infarction in young people. It is understood as a genetic disease that can prevent death in people in their 20s and 30s, and the standard for early intervention has been established.

Why is it Important?

What the two scientists left behind is the establishment that "an abnormality in a single cell membrane receptor can cause a systemic metabolic disorder."

The clear one-to-one correspondence between a gene, a protein, and a disease is a representative success story at the intersection of genetics, biochemistry, and clinical medicine. Subsequently, the causes of several other metabolic disorders have been elucidated using a similar approach.

This discovery has changed the entire landscape of cardiovascular preventive medicine. The advent of the statin era → reduction in the mortality rates of myocardial infarction and stroke → one of the core factors in extending the average human lifespan. The World Health Organization has included statins on its list of essential medicines.

The discovery also carries a strong symbolic meaning as an example of collaboration. The fact that Brown and Goldstein collaborated so closely that it was impossible for them to share the Nobel Prize for 25 years shows that science is not only the result of individual talent but also of continuous collaboration. And their reflection that this collaboration enriched their lives provides a strong message to young researchers today.

The flow of metabolic disease genetics after this award continues as follows:

• 1993: Roberts and Sharp — Split genes and mRNA splicing (provided the basis for diagnosis and treatment)
• 1994: Gilman and Rodbell — G protein-coupled receptors (expanded signal transduction)
• 2003: Human Genome Project — Completion of the genetic map of metabolic diseases
• 2011: GWAS (Genome-Wide Association Study) — Genetic analysis of polygenic cardiovascular diseases

The clinical establishment of this discovery:

• Statin series — from lovastatin (1987) to rosuvastatin (2003)
• Ezetimibe — FDA approved in 2002, inhibits cholesterol absorption in the small intestine
• PCSK9 inhibitors — Repatha and Praluent (2015), inclisiran (2021)
• CRISPR gene therapy — clinical trials in progress by VERVE Therapeutics, etc.

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