National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Yunis-Varon syndrome



Other Names:
Cleidocranial dysplasia, micrognathia, absent thumbs, & distal aphalangia; Yunis-Varón syndrome; Yunis Varon syndrome
Categories:

Yunis-Varon syndrome is a rare condition that affects many different parts of the body. Signs and symptoms are generally present from birth and may include underdeveloped or absent collarbones (clavicles); large fontanelles; characteristic facial features; hypotonia (reduced muscle tone) and/or abnormalities of the fingers and toes. Affected people may also experience feeding difficulties, breathing problems, brain malformations, heart defects, skeletal abnormalities, developmental delay, and/or intellectual disability.[1][2] Yunis-Varon syndrome is caused by changes (mutations) in the FIG4 gene and is inherited in an autosomal recessive manner.[3][4] Treatment is based on the signs and symptoms present in each person.[1][4]
Last updated: 4/13/2016

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Showing of 107 |
Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Aplasia of the distal phalanges of the hand
Absent outermost hand bone
0009881
Aplasia of the distal phalanx of the hallux
Absent outermost bone of big toe
0010102
Short proximal phalanx of hallux
Short innermost big toe bone
0010107
30%-79% of people have these symptoms
Abnormal parietal bone morphology 0002696
Abnormal pelvis bone morphology
Abnormal shape of pelvis bone
0040163
Abnormality of dental structure
Abnormality of tooth part
Abnormality of tooth structure
[ more ]
0011061
Abnormality of the occipital bone 0012294
Absent sternal ossification 0006628
Absent thumb
Absent thumbs
0009777
Agenesis of corpus callosum 0001274
Anteverted nares
Nasal tip, upturned
Upturned nasal tip
Upturned nose
Upturned nostrils
[ more ]
0000463
Aplasia of the 1st metacarpal
Absent 1st long bone of hand
0010035
Aplasia/hypoplasia of the 1st metatarsal
Absent/small 1st long bone of foot
Absent/underdeveloped 1st long bone of foot
[ more ]
0010067
Aplasia/Hypoplasia of the clavicles
Absent/small collarbone
Absent/underdeveloped collarbone
[ more ]
0006710
Aplasia/Hypoplasia of the nails
Absent/small nails
Absent/underdeveloped nails
[ more ]
0008386
Aplasia/Hypoplasia of the nipples
Absent/small nipples
Absent/underdeveloped nipples
[ more ]
0006709
Arrhinencephaly 0002139
Bilateral external ear deformity 0040111
Bilateral microphthalmos
Abnormally small eyeball on both sides
0007633
Broad secondary alveolar ridge 0000216
Cardiomegaly
Enlarged heart
Increased heart size
[ more ]
0001640
Cardiomyopathy
Disease of the heart muscle
0001638
Cataract
Clouding of the lens of the eye
Cloudy lens
[ more ]
0000518
Congenital microcephaly 0011451
Decreased skull ossification
Decreased bone formation of skull
0004331
Dolichocephaly
Long, narrow head
Tall and narrow skull
[ more ]
0000268
Generalized neonatal hypotonia
Generalized low muscle tone in neonate
0008935
Global developmental delay 0001263
High forehead 0000348
High, narrow palate
Narrow, high-arched roof of mouth
Narrow, highly arched roof of mouth
[ more ]
0002705
Hypertelorism
Wide-set eyes
Widely spaced eyes
[ more ]
0000316
Hypoplasia of the frontal lobes
Underdeveloped frontal lobe
0007333
Hypospadias 0000047
Low-set ears
Low set ears
Lowset ears
[ more ]
0000369
Metatarsus adductus
Front half of foot turns inward
0001840
Micrognathia
Little lower jaw
Small jaw
Small lower jaw
[ more ]
0000347
Micropenis
Short penis
Small penis
[ more ]
0000054
Neuronal loss in central nervous system
Loss of brain cells
0002529
Pachygyria
Fewer and broader ridges in brain
0001302
Postnatal growth retardation
Growth delay as children
0008897
Premature loss of primary teeth
Early loss of baby teeth
Premature loss of baby teeth
[ more ]
0006323
Proptosis
Bulging eye
Eyeballs bulging out
Prominent eyes
Prominent globes
Protruding eyes
[ more ]
0000520
Pulmonary arterial hypertension
Increased blood pressure in blood vessels of lungs
0002092
Redundant neck skin
Excess neck skin
Excess skin over the neck
Redundant skin folds of neck
Redundant skin over the neck
[ more ]
0005989
Rocker bottom foot
Rocker bottom feet
Rocker-bottom feet
Rockerbottom feet
[ more ]
0001838
Sclerocornea
Hardening of skin and connective tissue
0000647
Severe failure to thrive
Severe faltering weight
Severe weight faltering
[ more ]
0001525
Short chin
Decreased height of chin
Short lower third of face
[ more ]
0000331
Short middle phalanx of finger
Short middle bone of finger
0005819
Short philtrum 0000322
Short stature
Decreased body height
Small stature
[ more ]
0004322
Short upper lip
Decreased height of upper lip
Decreased vertical length of upper lip
Shortening of upper lip
[ more ]
0000188
Shortening of all distal phalanges of the toes
Shortening of all outermost bone of the toes
0005793
Single transverse palmar crease 0000954
Sparse eyebrow
Sparse eyebrows
0045075
Sparse eyelashes
Scant eyelashes
Scanty eyelashes
Thin eyelashes
[ more ]
0000653
Sparse scalp hair
Reduced/lack of hair on scalp
Scalp hair, thinning
Sparse, thin scalp hair
sparse-absent scalp hair
[ more ]
0002209
Syndactyly
Webbed fingers or toes
0001159
Tapered finger
Tapered fingertips
Tapering fingers
[ more ]
0001182
Thin vermilion border
Decreased volume of lip
Thin lips
[ more ]
0000233
Upslanted palpebral fissure
Upward slanting of the opening between the eyelids
0000582
Ventricular septal defect
Hole in heart wall separating two lower heart chambers
0001629
Wide cranial sutures
Large cranial suture
Persistent open cranial sutures
[ more ]
0010537
5%-29% of people have these symptoms
Aplasia/Hypoplasia of the scapulae
Absent/small shoulder blade
Absent/underdeveloped shoulder blade
[ more ]
0006713
Atrial septal defect
An opening in the wall separating the top two chambers of the heart
Hole in heart wall separating two upper heart chambers
[ more ]
0001631
Cerebellar hypoplasia
Underdeveloped cerebellum
Small cerebellum
[ more ]
0001321
Clitoral hypertrophy
Enlarged clitoris
0008665
Cryptorchidism
Undescended testes
Undescended testis
[ more ]
0000028
Flared metaphysis
Flared wide portion of long bone
0003015
Gingival recession 0030816
Glossoptosis
Retraction of the tongue
0000162
Hearing impairment
Deafness
Hearing defect
[ more ]
0000365
Hip dislocation
Dislocated hips
Dislocation of hip
[ more ]
0002827
Hydrocephalus
Too much cerebrospinal fluid in the brain
0000238
Hydrops fetalis 0001789
Hypoplastic labia majora
Small labia majora
Underdeveloped vaginal lips
[ more ]
0000059
Increased nuchal translucency 0010880
Narrow nasal base
Decreased width of base of nose
Decreased width of nasal base
Narrow base of nose
Thin base of nose
Thin nasal base
[ more ]
0012809
Polyhydramnios
High levels of amniotic fluid
0001561
Pyloric stenosis 0002021
Renal artery stenosis
Narrowing of kidney artery
0001920
Renovascular hypertension 0100817
Short ribs 0000773
Slender long bones with narrow diaphyses
Slender long bones with narrow shaft
0004993
1%-4% of people have these symptoms
Tetralogy of Fallot 0001636
Percent of people who have these symptoms is not available through HPO
Abnormality of blood and blood-forming tissues 0001871
Abnormality of the neck 0000464
Abnormality of the scapula
Abnormality of the shoulder blade
0000782
Absent nipple
Absent nipples
0002561
Aplasia/Hypoplasia of the distal phalanges of the hand
Absent/small outermost finger bone of the hand
Absent/underdeveloped outermost finger bone of the hand
[ more ]
0009835
Aplasia/Hypoplasia of the hallux
Absent/small big toe
Absent/underdeveloped big toe
[ more ]
0008362
Aplasia/Hypoplasia of the middle phalanges of the hand
Absent/small middle finger bone of the hand
Absent/underdeveloped middle finger bone of the hand
[ more ]
0009843
Aplastic clavicle
Absent collarbone
0006660
Autosomal recessive inheritance 0000007
Generalized hypotonia
Decreased muscle tone
Low muscle tone
[ more ]
0001290
Hypoplastic facial bones
Decreased size of facial bones
Decreased size of facial skeleton
[ more ]
0002692
Intrauterine growth retardation
Prenatal growth deficiency
Prenatal growth retardation
[ more ]
0001511
Large fontanelles
Wide fontanelles
0000239
Microcephaly
Abnormally small skull
Decreased circumference of cranium
Decreased size of skull
Reduced head circumference
Small head circumference
[ more ]
0000252
Premature birth
Premature delivery of affected infants
Preterm delivery
[ more ]
0001622
Severe global developmental delay 0011344
Short clavicles
Short collarbone
0000894
Short finger
Stubby finger
0009381
Short toe
Short toes
Stubby toes
[ more ]
0001831
Small earlobe
Small earlobes
0000385
Sparse and thin eyebrow
Thin, sparse eyebrows
0000535
Toe syndactyly
Fused toes
Webbed toes
[ more ]
0001770
Showing of 107 |
Last updated: 7/1/2020

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources


Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • The Centers for Mendelian Genomics program is working to discover the causes of rare genetic disorders. For more information about applying to the research study, please visit their website.

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

In-Depth Information

  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Yunis-Varon syndrome. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.


  1. Varghese P, Collins N, Warner G, Leitch J, Ho E & Crock P. Yunis-varon syndrome: further delineation of cardiovascular and endocrine outcome. Am J Med Genet A. May, 2014; 164A(5)::1213-7. http://www.ncbi.nlm.nih.gov/pubmed/24610892.
  2. Yunis Varon Syndrome. WebMD. 2015; http://www.webmd.com/children/yunis-varon-syndrome.
  3. Bharadwaj R, Cunningham KM, Zhang K & Lloyd TE. IG4 regulates lysosome membrane homeostasis independent of phosphatase function. Hum Mol Genet. February 15, 2016; 25(4):681-92. http://www.ncbi.nlm.nih.gov/pubmed/26662798.
  4. Campeau PM. Yunis-Varón Syndrome Is Caused by Mutations in FIG4, Encoding a Phosphoinositide Phosphatase. Am J Hum Genet. May 2, 2013; 92(5):781-791. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3644641/.