Mannose-binding lectin protein deficiency

Does mannose-binding lectin protein (MBL) deficiency increase the risk for autoimmune or other conditions?

Again, this is a very difficult question to answer definitively. It is known that not all those with MBL deficiency have symptoms. Therefore medical researchers believe deficiency of MBL is likely further influenced by other genetic and environmental factors that are currently poorly understood.

Many of the published studies of the effects of MBL deficiency have conflicting findings, with one study finding a increase in risk or severity associated with MBL, while another finds no effect or even a decreased risk. Several authors have suggested this is because those who are defined as having MBL deficiency differs markedly between the studies.

Overall, however, there seems to be agreement that increased susceptibility to infection is generally seen in patients with MBL deficiency when additional factors that compromise the immune system are present.

Since the MBL protein is involved in the inflammatory process, its deficiency has been studied in relation to autoimmune diseases. These are among the most conflicting studies, especially concerning the relation to [rheumatoid arthritis]( "

Ctrl+Click to follow link"), crohns disease and [diabetes]( "

Ctrl+Click to follow link"). Low levels of MBL do seem overall to increase the risk for developing [systemic lupus erythematosus]( erythematosus/Resources/1 " erythematosus/Resources/1

Ctrl+Click to follow link") (SLE or lupus). However, low levels of MBL may lower damage after cardiac, renal or cerebral ischemia and decrease the risk of organ rejection (though increase the risk of infection after transplantation).

Last updated on 05-01-20

What are the features and related conditions of 10q22.3q23.2 microdeletion syndrome?

The features of 10q22.3q23.2 microdeletion syndrome appear to be quite variable. Most commonly individuals with this microdelation have mild distinct facial features and speech and language delay, but the latter ranges from normal to severe. About 50% of known cases have had a congenital heart defect. Some children have been found to have [attention deficit hyperactivity disorder]( hyperactivity-disorder-adhd/index.shtml " disorder-adhd/index.shtml

Ctrl+Click to follow link") and a few have autism spectrum disorder. Less commonly cerebellar and breast developmental abnormalities may be present.

In addition to the features listed above, there has been concern that since the [BMPR1A]( "

Ctrl+Click to follow link") gene (located at 10q22.3) may be affected by this microdeletion, that individuals with this microdeletion may be at a higher risk of developing [juvenile polyposis syndrome]( syndrome/Resources/1 " polyposis-syndrome/Resources/1

Ctrl+Click to follow link")(JPS). However, published reports did not find this to be the case. Further studies indicate that [PTEN]( "

Ctrl+Click to follow link") (located at 10q23.3 which is just past your daughter's deletion) must also be affected for there to be an increased risk of JP. However medical researchers still suggest screening for JPS through adolescence is advised. Such screening may include a complete blood count, colonoscopy and upper gastrointestinal endoscopy beginning at 15 years of age or at initial symptoms such as gastrointestinal bleeding.

It is important to understand that all of this information comes from studied cases. Case reports document clinical findings associated with individual cases. The clinical findings documented in these case reports are based on specific individuals and may differ from one affected person to another. This is especially true with chromosomal microdeletions, as the exact breakpoints (and thus affected genes) varies for each individual.

Last updated on 05-01-20

Where can I find information about research studies and clinical trials involving treatments for mannose-binding lectin protein deficiency?

The U.S. National Institutes of Health, through the National Library of Medicine, developed to provide patients, family members, and members of the public with current information on clinical research studies. This site is updated regularly and may be checked often for updates. To find trials for mannose-binding lectin protein deficiency, click on the link above and use "mannose-binding lectin" as your search term. After you click on a study, review its "eligibility" criteria to determine its appropriateness. Use the study’s contact information to learn more.

You can also find relevant articles on mannose-binding lectin protein deficiency through PubMed, a searchable database of biomedical journal articles. Although not all of the articles are available for free online, most articles listed in PubMed have a summary available. To obtain the full article, contact a medical/university library or your local library for interlibrary loan. You can also order articles online through the publisher’s Web site. Using "mannose-binding lectin" as your search term should help you locate articles. Use the Advanced and Limits search features to narrow your search results. Click here to view a search.

The National Library of Medicine (NLM) Web site has a page for locating libraries in your area that can provide direct access to these journals (print or online). The Web page also describes how you can get these articles through interlibrary loan and Loansome Doc (an NLM document-ordering service). You can access this page at the following link: You can also contact the NLM toll-free at 888-346-3656 to locate libraries in your area.

Last updated on 05-01-20

What is mannose-binding lectin protein (MBL) deficiency?

Mannose-binding lectin (MBL) deficiency results in a decreased amount of a specific protein (mannan-binding protein) involved in the immune system. It was originally thought that MBL deficiency resulted in an increased susceptibility to infections. However, low levels of this protein have been found in many healthy people. MBL deficiency is more likely to be associated with infections in toddlers and those who have a weakened immune system (immunocompromised), including those with an underlying medical condition, cancer patients undergoing chemotherapy, and organ- transplant patients. Some studies have also suggested an association between severe MBL deficiency and recurrent infections. MBL deficiency is caused by changes in the MBL2 gene. However, it is important to note that changes in this gene are very common in the general population. Treatment for individuals with recurrent infections and MBL deficiency may include antibiotics to treat bacterial infections and regular vaccinations. Prophylactic antibiotics may be indicated in some cases.

Last updated on 05-01-20

How common is mannose-binding lectin protein (MBL) deficiency?

Mannose-binding lectin protein deficiency is thought to be fairly common, with a 3% frequency in the general population. The condition appears to be more common in certain populations; it may be present in about 5% of people of European descent and about 10% of sub-Saharan Africans.

Last updated on 05-01-20

Is there a link between mannose binding lectin protein deficiency and prenatal exposure to levaquin?

We were unable to find information in our search of the medical literature regarding an association between prenatal exposure of Levaquin and manose binding lectin protein deficiency. You can find details regarding Levaquin on the Web site at the following link:

Last updated on 05-01-20

How can I learn about research involving mannose-binding lectin protein (MBL) deficiency? lists trials that are studying or have studied mannose-binding lectin protein (MBL) deficiency. Click on the link to go to to read descriptions of these studies.

You can also contact the Patient Recruitment and Public Liaison (PRPL) Office at the National Institutes of Health (NIH). We recommend calling the toll-free number listed below to speak with a specialist, who can help you determine if your wife is eligible for any clinical trials.

Patient Recruitment and Public Liaison Office
NIH Clinical Center
Bethesda, Maryland 20892-2655
Toll-free: 1-800-411-1222
Fax: 301-480-9793
Web site:

You can find helpful general information on clinical trials at the following Web page.

Resources on many charitable or special-fare flights to research and treatment sites and low-cost hospitality accommodations for outpatients and family members, as well as ambulance services, are listed on the Web site of the Office of Rare Diseases (ORD), part of the National Institutes of Health.

Last updated on 05-01-20

If a person has mannose-binding lectin protein (MBL) deficiency, what are the chances he/she would pass the condition to his/her child?

MBL deficiency can occur as a result of one or more variations in the MBL2 gene, and is likely further influenced by other genetic and environmental factors that are currently poorly understood. Not everyone who inherits a MBL2 gene variation, however, develops signs and symptoms as a result of MBL deficiency. With our current knowledge, it is difficult to assess risks to future offspring. In the future, it is likely much more will be known regarding the genetics of MBL deficiency. We recommend discussing any questions or concerns with a genetics professional.

Last updated on 05-01-20

Could the mannose binding lectin (MBL) deficiency be associated with 10q22.3q23.2 microdeletion syndrome?

MBL deficiency is caused by changes or [mutations]( "

Ctrl+Click to follow link") in a single gene, MBL2. The location of MBL2 is 10q11.2 (the long arm of chromosome 10, band 11.2). MBL deficiency is not a rare disorder. It is estimated that MBL deficiency affects 5% (though some researchers suggest as high as 40%) of the population.

MBL2 gene is thus located much closer to the center of chromosome 10 than the 10q22.3q23.2 microdeletion so is not at least directly related. We were not able to find any reports mentioning a child with 10q22.3q23.2 microdeletion syndrome or any microdeletion in that region also being affected by the MBL deficiency. This is likely due to the small number of known cases of 10q22.3q23.2 microdeletion syndrome, because, since MBL deficiency is relatively common, it would not be surprising to find another child, like your daughter, who had both.

That said however, when very detailed molecular mapping of various microdeletions in the 10q22-q24 region were performed, it was found that the deletions were very complicated and involved rearrangement of other chromosomal material. Therefore it is difficult to state conclusively that there is no connection at the molecular level as our scientific understanding just is not to that level at this time.

Last updated on 05-01-20

Selected Full-Text Journal Articles

Mannose binding lectin protein deficiency

Eisen DP. Mannose-Binding Lectin Deficiency and Respiratory Tract Infection. J Innate Immun. 2010 Feb;2:114-122.

Last updated on 04-27-20

Name: Immune Deficiency Foundation 110 West Road, Suite 300
Towson, MD, 21204, United States
Toll Free: 1-800-296-4433 Fax : +1-410-321-9165 Email: Url:
Name: Immune Deficiencies Foundation Australia PO Box 969 Penrith NSW 2751
Phone: 800-100-198 Email: Url:
Name: American Autoimmune Related Diseases Association (AARDA) 22100 Gratiot Avenue
Eastpointe, MI, 48021, United States
Phone: 586-776-3900 Toll Free: 800-598-4668 Fax : 586-776-3903 Email: Url:

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