November 30, 2022
Years published: 2008, 2012, 2015, 2018, 2022
NORD gratefully acknowledges David A. Stevenson, MD, Professor, Stanford University, and Amy Calhoun, MD, Assistant Professor, University of Iowa, for assistance in the preparation of this report.
Lymphedema-distichiasis syndrome is a rare genetic multisystem disorder characterized by swelling of the legs because of fluid accumulation and the development of extra eyelashes (distichiasis). Distichiasis may range from a few extra lashes to a full set of extra eyelashes. Swelling most often affects both legs (bilateral) and usually occurs around puberty. Additional anomalies sometimes associated with this disorder include early onset varicose veins, droopy eyelids (ptosis), heart defects, cleft palate, abnormal heart rhythm and abnormal curvature of the spine (scoliosis). Lymphedema-distichiasis syndrome is caused by changes (pathogenic variants) of the FOXC2 gene and is inherited in an autosomal dominant pattern.
The symptoms of lymphedema-distichiasis vary greatly from person to person even among members of the same family. The most common finding is the extra row of eyelashes (distichiasis). Most patients also develop swelling (edema) or puffiness of the legs because of the accumulation of protein-rich fluid (lymph) in the soft layers of tissue under the skin.
The severity of lymphedema (swelling due to the accumulation of lymph fluid) varies, but usually involves only the legs. In most people, both legs are affected (bilateral). In some people, swelling may cause tightness, discomfort and unusual tingling sensations (paresthesias) in the affected areas. Typically, lymphedema develops around puberty, although it can develop as early as before the person is born or in adulthood.
Males develop lymphedema at an earlier age than females and are more likely to develop cellulitis. Cellulitis is an infection that is often associated with lymphedema. Cellulitis is characterized by swollen, reddened skin that may feel warm and tender.
Distichiasis may range from a few extra lashes to a full set of extra eyelashes. This can be very hard to see and is often missed by routine examination. Associated eye abnormalities may occur including an abnormal sensitivity to light (photophobia), inflammation of the delicate membrane that lines the inside of the eyelids (conjunctivitis), irritation of the curved transparent outer layer of fibrous tissue covering the eyeball (cornea) and the development of a small tender bump on the eyelid (stye). Drooping or sagging of the eyelids (ptosis) may also occur.
Many individuals with lymphedema-distichiasis syndrome develop varicose veins, a condition marked by twisted, widened and enlarged veins just below the surface of the skin. In some people, varicose veins may precede the development of lymphedema. In individuals with lymphedema-distichiasis syndrome, varicose veins develop at a much younger age and with greater frequency than in the general population.
Congenital heart disease has been reported in some individuals with lymphedema-distichiasis syndrome, especially a condition known as tetralogy of Fallot. Tetralogy of Fallot consists of a combination of four different heart defects: a ventricular septal defect; obstructed outflow of blood from the right ventricle to the lungs (pulmonary stenosis); a displaced aorta, which causes blood to flow into the aorta from both the right and left ventricles; and the abnormal enlargement of the right ventricle. This combination of abnormalities typically leads to poor blood flow to the lungs and poor blood oxygenation. The symptoms tend to worsen with time if this remains untreated and can be life-threatening.
In some patients, irregular heartbeats (arrhythmias) may develop.
Rarely, additional abnormalities have been reported to occur in association with lymphedema-distichiasis syndrome including crossed eyes (strabismus), incomplete closure of the roof of the mouth (cleft palate), side-to-side curvature of the spine (scoliosis), webbing of the neck, and cysts on the outermost layer of the membranes (meninges) that cover the spinal cord (spinal extradural cysts). Very rarely, patients may have total body swelling prior to birth (hydrops fetalis). Also very rarely, patients may have breathing problems due to abnormal lymph flow in their lungs.
Lymphedema-distichiasis syndrome occurs due to variants that disrupt/change the forkhead family transcription factor (FOXC2) gene. It is currently unknown exactly how variants in this gene lead to the symptoms of lymphedema-distichiasis syndrome, but the variants are thought to result in loss-of-function.
Lymphedema is caused by the accumulation of protein-rich fluid (lymph) in areas of the body, typically due to dysfunction or abnormality of the lymphatic system. The lymphatic system is a circulatory network of vessels, ducts, and nodes that filter and distribute lymph and blood cells throughout the body. In lymphedema-distichiasis syndrome it is possible that the lymphedema develops due to obstruction, malformation, underdevelopment (hypoplasia) or improper function of various lymphatic vessels. One group of researchers, Mellor et al., showed that the venous valves failed in both the superficial and deep veins in the lower limbs of individuals with FOXC2 variants suggesting that the FOXC2 gene is important for the normal development and maintenance of venous and lymphatic valves. Their group also showed that lymph vessel function in people with lymphedema distichiasis syndrome was negatively affected by gravity, possibly explaining why the legs are primarily affected when the variant is present in every cell in the body.
Lymphedema-distichiasis syndrome is an autosomal dominant genetic disorder. Dominant genetic disorders occur when only a single copy of an abnormal gene is necessary to cause a particular disease. The abnormal gene can be inherited from either parent or can be the result of a mutated gene in the affected individual. The risk of passing the abnormal gene from an affected parent to an offspring is 50% for each pregnancy. The risk is the same for males and females.
Lymphedema-distichiasis affects males and females in equal numbers. Lymphedema develops in males at an earlier age than females. The prevalence of this disorder in the general population is unknown. Lymphedema-distichiasis syndrome may go undiagnosed making it difficult to determine its true frequency in the general population.
A diagnosis of lymphedema-distichiasis syndrome is primarily made based upon a thorough clinical evaluation, a detailed patient history and the identification of characteristic findings (i.e., primary lymphedema, distichiasis). FOXC2 molecular testing is available clinically to help confirm a diagnosis. A variety of specialized tests may be performed to determine the extent of the disorder. Such tests include lymphoscintigraphy or an echocardiogram. During lymphoscintigraphy, a substance known as a contrast medium is injected into a lymphatic vessel (usually in a hand or foot). A series of x-rays are taken that show the medium as it moves through the lymphatic vessels giving physicians a picture of the health and structure of the lymphatic vessels. During an echocardiogram, reflected sounds waves are used to create an image of the heart, which can reveal congenital heart defects potentially associated with lymphedema-distichiasis syndrome.
The treatment of lymphedema-distichiasis syndrome is directed toward the specific symptoms that are apparent in each individual. Treatment is aimed at reducing swelling and preventing infection. Complete decongestive therapy (CDT) is a form of treatment in which specialized massage techniques are coupled with therapeutic bandaging, meticulous skin care, exercise and the use of well-fitted compression garments such as fitted stockings. Antibiotics may be used to treat recurrent infections such as cellulitis or as a preventive (prophylactic) measure in individuals with recurrent infections.
Distichiasis may be managed with lubrication or plucking (epilation). More definitive treatments for distichiasis include cryotherapy, electrolysis or lid splitting. Cryotherapy is the application of extreme cold to destroy diseased tissue. Electrolysis uses a short-wave radio frequency to destroy the extra eyelashes. Lip splitting is a surgical procedure in which the eyelid is split open to expose the root (follicle) of the eyelashes. Each extra eyelash is then removed (excised). In some cases, cryotherapy or electrolysis is used in conjunction with lid splitting.
In some patients, surgery may be performed to treat other abnormalities such as ptosis or cleft palate. Individuals with heart abnormalities may be monitored regularly.
Genetic counseling is recommended for affected individuals and their families. Other treatment is symptomatic and supportive.
Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government web site.
For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:
Tollfree: (800) 411-1222
TTY: (866) 411-1010
Some current clinical trials also are posted on the following page on the NORD website:
For information about clinical trials sponsored by private sources, contact:
For information about clinical trials conducted in Europe, contact:
de Bruyn G, Casaer A, Devolder K, et al. Hydrops fetalis and pulmonary lymphangiectasia due to FOXC2 mutation: an autosomal dominant hereditary lymphedema syndrome with variable expression. Eur J Pediatr. 2012;171(3):447-50.
Mellor RH, Tate N, Stanton AWB, Hubert C, Maekinen T, Smith A, Burnand K, Jeffery S, Levick JR, Mortimer PS; Mutations in FOXC2 in humans (lymphedema distichiasis syndrome) cause lymphatic dysfunction on dependency. J Vasc Res. 2011; 44:381-4.
Shimoda H, Bernas MJ, Witte MH. Dysmorphogenesis of lymph nodes in foxc2 haploinsufficient mice. Histochem Cell Biol. 2011;135(6):603-13.
Sanches-Carpintero R, Dominguez P, Nunez MT, Patino-Garcia A, Spinal extradural arachnoid cysts in lymphedema-distichiasis syndrome. Genet Med. 2010; 12: 532-5.
Connell F, Brice G, Jeffery S, Keely V, Mortimper P, Mansur S. A new classification system for primary lymphatic dysplasias based on phenotype. Clin Genet. 2010; 77:438-452.
Connell F, Brice G, Mortimer P. Phenotypic characterization of primary lymphedema. Ann NY Acad Sci. 2008;1131:140-6.
Mellor RH, Brice G, Stanton AW, French J, Smith A, Jeffery S, Levick JR, Burnand KG, Mortimer PS; Lymphoedema Research Consortium. Mutations in FOXC2 are strongly associated with primary valve failure in veins of the lower limb. Circulation. 2007;115:1912-20.
Berry FB, Tamimi Y, Carle MV, Lehmann OJ, Walter MA. The establishment of a predictive mutational model of the forkhead domain through the analyses of FOXC2 missense mutations identified in patients with hereditary lymphedema with distichiasis. Hum Mol Genet. 2005;14:2619-27.
Kriederman BM, Myloyde TL, Witte MH, et al., FOXC2 haploinsufficient mice are a model for human autosomal dominant lymphedema-distichiasis syndrome. Hum Mol Genet. 2003;12:1179-85.
Brice GW, Mansour S, Bell R, et al., Analysis of phenotypic abnormalities in lymphoedema-distichiasis syndrome in 74 patients with FOXC2 mutations or linkage to 16q24. J Med Genet. 2002;39:478-83.
Erickson RP, Dagenais SL, Caulder MS, et al., Clinical heterogeneity in lymphoedema-distichiasis syndrome with FOXC2 truncating mutations. J Med Genet. 2001;38:761-6.
Fang J, Dagenais SL, Erickson RP, et al., Mutations in FOXC2 (MFH-1), a forkhead family transcription factor, are responsible for the hereditary lymphedema-distichiasis syndrome. Am J Med Genet. 2000;67:1382-8.
Mangion J, Rahman N, Mansour S, et al., A gene for lymphedema-distichiasis maps to 16q24.3. Am J Hum Genet. 1999;65:427-32.
Van Zanten M, Mansour S, Ostergaard P, et al. Milroy Disease. 2006 Apr 27 [Updated 2021 Feb 18]. In: Adam MP, Everman DB, Mirzaa GM, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2022. Available from: https://www.ncbi.nlm.nih.gov/books/NBK1239/ Accessed Nov 30, 2022.
Online Mendelian Inheritance in Man (OMIM). The Johns Hopkins University. Lymphedema, Hereditary, II. Entry No: 153200. Last Edited 01/10/2019. Available at: http://omim.org/entry/153200 Accessed Nov 30, 2022.
Online Mendelian Inheritance in Man (OMIM). The Johns Hopkins University. Lymphedema, Hereditary, IA. Entry No: 153100. Last Edited 08/23/2022. Available at: http://omim.org/entry/153100 Accessed Nov 30, 2022.
Online Mendelian Inheritance in Man (OMIM). The Johns Hopkins University. Lymphedema-Distichiasis Syndrome. Entry No: 153400. Last Edited 05/16/2019. Available at: http://omim.org/entry/153400 Accessed Nov 30, 2022.
NORD strives to open new assistance programs as funding allows. If we don’t have a program for you now, please continue to check back with us.
NORD and MedicAlert Foundation have teamed up on a new program to provide protection to rare disease patients in emergency situations.Learn more https://rarediseases.org/patient-assistance-programs/medicalert-assistance-program/
Ensuring that patients and caregivers are armed with the tools they need to live their best lives while managing their rare condition is a vital part of NORD’s mission.Learn more https://rarediseases.org/patient-assistance-programs/rare-disease-educational-support/
This first-of-its-kind assistance program is designed for caregivers of a child or adult diagnosed with a rare disorder.Learn more https://rarediseases.org/patient-assistance-programs/caregiver-respite/