Hudson Freeze PhD

Hudson “Hud” H. Freeze, PhD, is a professor of glycobiology and director of the Sanford Children’s Health Research Center at Sanford Burnham Prebys. Since joining the Institute in 1988, he has pioneered research into congenital disorders of glycosylation (CDG), a group of rare inherited diseases. His laboratory has discovered and characterized more than 30 types of CDG, advancing the diagnosis, treatment and understanding of these complex disorders.

Freeze’s scientific contributions began as an undergraduate at Indiana University, where he isolated Thermus aquaticus, a heat-loving bacterium from Yellowstone National Park. The discovery ultimately led to the development of Taq polymerase, an enzyme essential to the polymerase chain reaction (PCR), which revolutionized genetic research. His early scientific journey was featured in an episode of NPR’s Radiolab.

His subsequent research at UC San Diego helped identify a unique phosphodiester form of mannose-6-phosphate, a key component of lysosomal enzyme targeting in humans. This discovery helped lay the groundwork for his later research into rare genetic disorders.

At Sanford Burnham Prebys, Freeze has translated fundamental discoveries into treatments for patients with rare diseases. He developed the first treatment for a child with phosphomannose isomerase deficiency (CDG-Ib) using oral mannose supplementation and helped pioneer dietary fucose therapy for leukocyte adhesion deficiency. Working with the NIH Undiagnosed Diseases Program and Network, his laboratory has helped diagnose approximately 275 patients with CDG.

A dedicated advocate for patients and families, Freeze works closely with organizations including CDG CARE and The GLUT1 Deficiency Foundation. He has published more than 350 scientific articles and received numerous honors, including the 2013 Golden Goose Award for his role in the discovery of Thermus aquaticus, the Rosalind Kornfeld Award and the Society for Glycobiology’s 2026 Karl Meyer Lectureship Award, its highest honor. He is also a fellow of the American Association for the Advancement of Science (AAAS) and has served as president of the Society for Glycobiology and the Federation of American Societies for Experimental Biology (FASEB).

Related Disease
Cancer, Congenital Disorders of Glycosylation, Crohn’s Disease (Colitis), Glycosylation-Related Disorders

Dr. Freeze’s research focuses on the pathology resulting from faulty glycosylation, the process of adding carbohydrate (sugar) chains to proteins and lipids. Carbohydrates are required for proper secretion and targeting of thousands of proteins – an often over looked fact of biology. He is driven by the search for novel therapeutics to treat patients with mutations leading to glycosylation defects called Congenital Disorders of Glycosylation (CDG). 

Hudson Freeze’s Research Report

Glycosylation: An Essential Function

The entire cell surface is coated with sugars in complex chains that promote (or sometimes interfere) with cell-to-cell communication. These sugar chains are first attached to proteins deep inside the cell where they help them get into shape for their jobs. As the proteins percolate toward to cell surface and beyond, the sugar chains are sculpted for specific needs. This entire process, called glycosylation, recruits a force of more than 500 genes for this job. The Freeze lab works on several facets of glycosylation, all of them with an eye toward therapeutic applications for diseases that impair the functions of these critical genes. 

Human Glycosylation Disorders

We focus is on a group of metabolic diseases called Congenital Disorders of Glycosylation (CDG). Today we know of defects in over 140 genes, well over double those known only 10 years ago. Patients with these diseases have highly variable mental and motor developmental delay, seizures, failure to grow, hypoglycemia (low blood sugar), clotting and digestion abnormalities and skeletal abnormalities to name just a few. These are rare disorders having a few thousand known patients worldwide, but it is likely that many remain undiagnosed, especially in developing countries.

Growing Awareness
Physicians are becoming more aware of glycosylation disorders in general, and basic scientists continue to discover sugar chains at the helm of many basic metabolic processes. Defective glycosylation is also known to cause 15 types of muscular dystrophy.

Working with CDG Kids
Rocket: We helped diagnose this young man over 10 years ago, and although he tragically passed away, his gentle face still reminds us of who we work for.  

Brianna: Sometimes our work leads to brighter outcomes as in the case of Brianna who we met over 20 years ago and treated with a simple therapy.  

Our Collaborations
The Freeze lab not only identifies new glycosylation disorders, but also tries to understand how these defects cause the disease manifestations. Defects occur in genes that activate and transport sugars, assemble them into glycans and remodel them. Some also traffic and distribute the glycosylation machinery within cells. Ongoing collaborations with academic physicians provide a steady flow of new patients for analysis. Since very few laboratories in the United States work on CDG, we are developing new molecular diagnostic methods to handle the increasing number of patients. Increased awareness of CDG in the medical community generated expanded government funding that allies us with 10 medical centers in the US seeking additional patients to study their natural history, develop biomarkers and test emerging therapies. Those avenues along with the help of generous philanthropic support, enables us to extend efforts to supplement the depleted glycosylation pathways in patients. 

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