Hennekam Syndrome
   HOME
*





Hennekam Syndrome
Hennekam syndrome also known as intestinal lymphagiectasia–lymphedema–mental retardation syndrome, is an autosomal recessive disorder consisting of intestinal lymphangiectasia, facial anomalies, peripheral lymphedema, and mild to moderate levels of growth and intellectual disability. It is also known as "lymphedema-lymphangiectasia-mental retardation syndrome". Hennekam Syndrome is subdivided according to the causative genetic lesion, most (or all) of which are affecting the VEGF-C/VEGFR-3 signaling pathway: * Type 1 (mutations in CCBE1) * Type 2 (mutations in FAT4) * Type 3 (mutations in ADAMTS3) The first recognition of a genetic association was with CCBE1, published by its namesake, Raoul Hennekam. The molecular mechanism of the lymphedema phenotype in CCBE1-associated cases was identified as a diminished ability of the mutated CCBE1 to accelerate and focus the activation of the primary lymphangiogenic growth factor VEGF-C. Mutations in the FAT4 gene had previously be ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Autosomal Recessive
In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The first variant is termed dominant and the second recessive. This state of having two different variants of the same gene on each chromosome is originally caused by a mutation in one of the genes, either new (''de novo'') or inherited. The terms autosomal dominant or autosomal recessive are used to describe gene variants on non-sex chromosomes ( autosomes) and their associated traits, while those on sex chromosomes (allosomes) are termed X-linked dominant, X-linked recessive or Y-linked; these have an inheritance and presentation pattern that depends on the sex of both the parent and the child (see Sex linkage). Since there is only one copy of the Y chromosome, Y-linked traits cannot be dominant or recessive. Additionally, there are other forms of dominance such as incomplete d ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Lymphedema
Lymphedema, also known as lymphoedema and lymphatic edema, is a condition of localized swelling caused by a compromised lymphatic system. The lymphatic system functions as a critical portion of the body's immune system and returns interstitial fluid to the bloodstream. Lymphedema is most frequently a complication of cancer treatment or parasitic infections, but it can also be seen in a number of genetic disorders. Though incurable and progressive, a number of treatments may improve symptoms. Tissues with lymphedema are at high risk of infection because the lymphatic system has been compromised. While there is no cure, treatment may improve outcomes. This commonly include compression therapy, good skin care, exercise, and manual lymphatic drainage (MLD), which together are known as combined decongestive therapy. Diuretics are not useful. Signs and symptoms The most common manifestation of lymphedema is soft tissue swelling, edema. As the disorder progresses, worsening edema a ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Growth Retardation
Delayed milestone, also called developmental delays, is used to describe the condition where a child does not reach one of these stages at the expected age. However, in most cases, a wide variety of ages can be considered normal, and not a cause for medical concern. Milestones are often measured using percentiles, and for many milestones a value between the 5th and 95th percentile does not require intervention, though values towards the edges of that range can be associated with other medical conditions. It is not possible to treat. It has been suggested that measurement of posture sway may be an early indicator. References External links - Information for parents on early childhood development and developmental disabilities "Recognizing Developmental Delays in Children" WebMD WebMD is an American corporation known primarily as an online publisher of news and information pertaining to human health and well-being. The site includes information pertaining to drugs. It is one ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Intellectual Disability
Intellectual disability (ID), also known as general learning disability in the United Kingdom and formerly mental retardation,Rosa's Law, Pub. L. 111-256124 Stat. 2643(2010). is a generalized neurodevelopmental disorder characterized by significantly impaired intellectual and adaptive functioning. It is defined by an IQ under 70, in addition to deficits in two or more adaptive behaviors that affect everyday, general living. Intellectual functions are defined under DSM-V as reasoning, problem‑solving, planning, abstract thinking, judgment, academic learning, and learning from instruction and experience, and practical understanding confirmed by both clinical assessment and standardized tests. Adaptive behavior is defined in terms of conceptual, social, and practical skills involving tasks performed by people in their everyday lives. Intellectual disability is subdivided into syndromic intellectual disability, in which intellectual deficits associated with other medical and be ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


CCBE1
Collagen and calcium-binding EGF domain-containing protein 1 is a protein that in humans is encoded by the ''CCBE1'' gene. Function CCBE1 is a regulator of the development and growth of the lymphatic system. CCBE1 is necessary for the proteolytic activation of VEGF-C Vascular endothelial growth factor C (VEGF-C) is a protein that is a member of the platelet-derived growth factor / vascular endothelial growth factor (PDGF/VEGF) family. It is encoded in humans by the ''VEGFC'' gene, which is located on chromosom ... by ADAMTS3, which is the main growth factor for the lymphatic system. Clinical significance Hennekam syndrome type I (a generalized lymphatic dysplasia in humans) is associated with mutations in the CCBE1 gene, and the molecular etiology of the disease has been elucidated. References External links * Further reading

* * * * * * * * {{gene-18-stub ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


FAT4
Protocadherin Fat 4, also known as cadherin family member 14 (CDHF14) or FAT tumor suppressor homolog 4 (FAT4), is a protein that in humans is encoded by the ''FAT4'' gene. FAT4 is associated with the Hippo signaling pathway. Clinical significance Mutations in FAT4 are associated to Hennekam syndrome Hennekam syndrome also known as intestinal lymphagiectasia–lymphedema–mental retardation syndrome, is an autosomal recessive disorder consisting of intestinal lymphangiectasia, facial anomalies, peripheral lymphedema, and mild to moderate le .... References Further reading

* * * * * * * * {{gene-4-stub ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




ADAMTS3
A disintegrin and metalloproteinase with thrombospondin motifs 3 is an enzyme that in humans is encoded by the ''ADAMTS3'' gene. The protein encoded by this gene is the major procollagen II N-propeptidase. Structure This gene encodes a member of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) protein family. Members of the family share several distinct protein modules, including a propeptide region, a metalloproteinase domain, a disintegrin-like domain, and a thrombospondin type 1 (TS) motif. Individual members of this family differ in the number of C-terminal TS motifs, and some have unique C-terminal domains. The protein encoded by this gene is the major procollagen II N-propeptidase. Function Because of the high similarity to ADAMTS2, the major substrate of ADAMTS3 had been erroneously assumed to be procollagen II. However, ADAMTS3 appears largely irrelevant for collagen maturation but instead is required for the activation of the lymphangioge ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


VEGF-C
Vascular endothelial growth factor C (VEGF-C) is a protein that is a member of the platelet-derived growth factor / vascular endothelial growth factor (PDGF/VEGF) family. It is encoded in humans by the ''VEGFC'' gene, which is located on chromosome 4q34. Functions The main function of VEGF-C is to promote the growth of lymphatic vessels (lymphangiogenesis). It acts on lymphatic endothelial cells (LECs) primarily via its receptor VEGFR-3 promoting survival, growth and migration. It was discovered in 1996 as a ligand for the orphan receptor VEGFR-3. Soon thereafter, it was shown to be a specific growth factor for lymphatic vessels in a variety of models. However, in addition to its effect on lymphatic vessels, it can also promote the growth of blood vessels and regulate their permeability. The effect on blood vessels can be mediated via its primary receptor VEGFR-3 or its secondary receptor VEGFR-2. Apart from vascular targets, VEGF-C is also important for neural development and bl ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Lymphangiogenesis
Lymphangiogenesis is the formation of lymphatic vessels from pre-existing lymphatic vessels in a method believed to be similar to angiogenesis (blood vessel development). Lymphangiogenesis plays an important physiological role in homeostasis, metabolism and immunity. Impaired or excessive lymphatic vessel formation has been implicated in a number of pathological conditions including neoplasm metastasis, oedema, rheumatoid arthritis, psoriasis, lymphangiomatosis and impaired wound healing. The role of the lymphatic system in these diseases has received renewed interest largely due to the discovery of lymphatic endothelial cell (LEC)-specific markers such as podoplanin, LYVE-1, PROX1, desmoplakin and VEGF-C receptor VEGFR-3. These specific markers have enabled insights into functional and molecular lymphatic biology. There are several known pro-lymphangiogenesis inducers such as VEGF-C, hyaluronic acid and ephrin-B2 Ephrin-B2 is a protein that in humans is encoded by the ''EFNB2'' ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]