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D-bifunctional Protein Deficiency

What is D-Bifunctional Protein Deficiency?

D-bifunctional protein deficiency, also known as peroxisomal bifunctional enzyme deficiency, is an inherited disease causing severe biochemical abnormalities that are usually fatal within the first two years of life.

Infants with D-bifunctional protein deficiency are floppy at birth with poor muscle tone. Most experience seizures shortly after birth and almost all develop seizures within the first few months of life. The majority show visual and hearing impairment and have severe intellectual disability. Few infants with D-bifunctional protein deficiency reach any developmental milestones or develop motor skills. Brain scans of these infants typically find a range of physical abnormalities. Infants with D-bifunctional protein deficiency also tend to share characteristic facial features.

D-bifunctional protein deficiency is the most severe among a group of diseases known as peroxisomal fatty acid oxidation disorders. Peroxisomes are structures that help detoxify our cells.

How common is D-Bifunctional Protein Deficiency?

D-bifunctional protein deficiency is extremely rare, but is estimated to affect 1 in 100,000 newborns.

How is D-Bifunctional Protein Deficiency treated?

There is no successful treatment for D-bifunctional protein deficiency. Treatment can only serve to address seizures with medication and ensure proper nutrition.

What is the prognosis for a person with D-Bifunctional Protein Deficiency?

The prognosis is poor. Most children with D-bifunctional protein deficiency die within the first two years of life without developing any mental or motor skills.


Fatty Oxidation Disorders Family Support Group

An all volunteer 501c3 non-profit dedicated to providing support, information and international networking for families affected by a Fatty Oxidation Disorder, as well as for professionals working with FOD families.

Director, Deb Lee Gould, MEd
PO Box 54
Okemos, MI 48805-0054
Phone: (517) 381-1940 (8am-8pm EST)
Skype: fodgroup

Online Mendelian Inheritance in Man

A database of human genes and genetic disorders authored and edited by scientists at Johns Hopkins and elsewhere and developed for the Web by the National Center for Biotechnology Information. Please note that the language is directed at scientists.

Other names for D-bifunctional Protein Deficiency

  • Peroxisomal Bifunctional Enzyme Deficiency