Focal dermal hypoplasia

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Disease Profile

<1 / 1 000 000

US Estimated

Europe Estimated

Age of onset

Neonatal

ICD-10

Q82.8

Inheritance

Focal dermal hypoplasia is caused by mutations in the PORCN gene and is inherited in an X-linked dominant manner. Many cases of focal dermal hypoplasia result from a new mutation and occur in people with no history of the disorder in their family ^[3] For a woman affected with focal dermal hypoplasia, the theoretical risk of passing the mutation to each of her offspring is 50%; however, many males with this condition do not survive. In addition, there are cases in which a woman may have the focal dermal hypoplasia mutation in some but not all of her egg cells, a condition known as germline mosaicism. In this case the risk of passing along the mutation may be as high as 50% depending on the level of mosaicism. Males with focal dermal hypoplasia typically have the mutation in some but not all of their cells. The risk that a male with FDH will pass the condition on to his daughters may be as high as 100%; men do not pass this condition on to their sons.^[2] We recommend discussing specific concerns with a genetics professional, who can help you understand how this condition might be inherited in your family. Click on the following link for resources for finding a genetics professional.

Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.

Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.

X-linked
dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.

X-linked
recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.

Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.

Not applicable

Other names (AKA)

DHOF; FODH; FDH;

Summary

Focal dermal hypoplasia is a genetic disorder that primarily affects the skin, skeleton, eyes, and face. The skin abnormalities are present from birth and can include streaks of very thin skin (dermal hypoplasia), cutis aplasia, and telangiectases. They also may abnormalities in the nails, hands, and feet. Some of the eye findings present may include small eyes (microphthalmia), absent or severely underdeveloped eyes (anophthalmia), and problems with the tear ducts. People with focal dermal hypoplasia may also have distinctive facial features such as a pointed chin, small ears, notched nostrils, and a slight difference in the size and shape of the right and left sides of the face (facial asymmetry). Most individuals with this condition are female. Males usually have milder signs and symptoms than females. Although intelligence is typically unaffected, some individuals have intellectual disability. This condition is caused by mutations in the PORCN gene and is inherited in an X-linked dominant manner. Most cases of focal dermal hypoplasia in females result from new mutations in the PORCN gene and occur in people with no history of the disorder in their family. When focal dermal hypoplasia occurs in males, it always results from a new mutation in this gene that is not inherited.^[1] Treatment is based on the signs and symptoms present in the person; however, care usually involves a team of specialists, including dermatologists, otolaryngologist, physical/occupational therapists, and hand surgeons.^[2]

Symptoms

Focal dermal hypoplasia is usually evident from birth and primarily affects the skin, skeleton, eyes, and face. The signs and symptoms of vary widely, although almost all affected individuals have skin abnormalities.^[1]

Some of the skin findings include streaks of very thin skin (dermal hypoplasia), yellowish-pink nodules of fat under the skin, areas where the top layers of skin are absent (cutis aplasia), telangiectases, and streaks of slightly darker or lighter skin. These skin features can cause pain, itching, irritation, or lead to skin infections. With age, most develop wart-like growths, called papillomas, around the nostrils, lips, anus, and female genitalia. They may also be present in the throat, specifically in the esophagus or larynx, and can cause problems with swallowing, breathing, or sleeping. Other features include small, ridged fingernails and toenails as well as sparse, brittle or absent scalp hair.^[1]

The skeleton is usually affected as well. Many individuals have hand and foot abnormalities, including missing fingers or toes (oligodactyly), webbed or fused fingers or toes (syndactyly), and a deep split in the hands or feet with missing fingers or toes and fusion of the remaining digits (ectrodactyly). X-rays can show streaks of altered bone density, called osteopathia striata, which usually do not cause symptoms.^[1]

Eye abnormalities are common and can include microphthalmia and anopthalmia as well as problems with the tear ducts. The retina or the optic nerve can also be incompletely developed, which can result in a gap or split in these structures (coloboma). Some of these eye abnormalities do not impair vision, while others can lead to low vision or blindness.^[1]

People with focal dermal hypoplasia often have distinctive, but subtle facial features such as a pointed chin, small ears, notched nostrils, and a slight difference in the size and shape of the right and left sides of the face (facial asymmetry). Some individuals may have a cleft lip and/or palate.^[1]

About half of those with focal dermal hypoplasia have teeth abnormalities of their teeth, especially of the enamel (the hard, white material that forms the protective outer layer of each tooth). Less commonly, kidney and gastrointestinal abnormalities are present. The kidneys may be fused together, which can lead to kidney infections. The main gastrointestinal abnormality that is seen is an omphalocele.^[1]

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.

Medical Terms

Other Names

Learn More:

HPO ID

80%-99% of people have these symptoms

Abnormal palmar dermatoglyphics

0001018

Abnormality of dental enamel

Abnormal tooth enamel

Enamel abnormalities

Enamel abnormality

[ more ]

0000682

Abnormality of dental morphology

Abnormality of dental shape

Abnormally shaped teeth

Deformity of teeth

Dental deformity

Dental malformations

Malformed teeth

Misshapen teeth

Misshapened teeth

[ more ]

0006482

Abnormality of epiphysis morphology

Abnormal shape of end part of bone

0005930

Abnormality of skin pigmentation

Abnormal pigmentation

Abnormal skin color

Abnormal skin pigmentation

Abnormality of pigmentation

Pigmentary changes

Pigmentary skin changes

Pigmentation anomaly

[ more ]

0001000

Abnormality of the middle ear

0000370

Abnormality of the nail

0001597

Camptodactyly of finger

Permanent flexion of the finger

0100490

Coarse metaphyseal trabecularization

0100670

Dermal atrophy

Skin degeneration

0004334

Finger syndactyly

0006101

Hand polydactyly

Extra finger

0001161

Hearing impairment

Deafness

Hearing defect

[ more ]

0000365

Lower limb asymmetry

Left and right leg differ in length or width

0100559

Low-set ears

Low set ears

Lowset ears

[ more ]

0000369

Macule

Flat, discolored area of skin

0012733

Papilloma

0012740

Reduced number of teeth

Decreased tooth count

0009804

Split foot

Lobster-claw foot deformity

Split-foot

[ more ]

0001839

Split hand

Claw hand

Claw hand deformities

Claw hands

Claw-hand deformities

Split-hand

[ more ]

0001171

Telangiectasia of the skin

0100585

Thin skin

0000963

Toe syndactyly

Fused toes

Webbed toes

[ more ]

0001770

Upper limb asymmetry

Unequal size of arms

0100560

30%-79% of people have these symptoms

Alopecia

Hair loss

0001596

Chorioretinal coloboma

Birth defect that causes a hole in the innermost layer at the back of the eye

0000567

Cognitive impairment

Abnormality of cognition

Cognitive abnormality

Cognitive defects

Cognitive deficits

Intellectual impairment

Mental impairment

[ more ]

0100543

Corneal opacity

0007957

Diastasis recti

Gap between large left and right abdominal muscles

0001540

Ectopia lentis

0001083

Erythema

0010783

Facial asymmetry

Asymmetry of face

Crooked face

Unsymmetrical face

[ more ]

0000324

Horseshoe kidney

Horseshoe kidneys

0000085

Hypoplasia of the iris

Underdeveloped iris

0007676

Hypoplastic pelvis

0008839

Iris coloboma

Cat eye

0000612

Microphthalmia

Abnormally small eyeball

0000568

Multicystic kidney dysplasia

0000003

Open bite

Absence of overlap of upper and lower teeth

Open bite between upper and lower teeth

[ more ]

0010807

Scoliosis

0002650

Short clavicles

Short collarbone

0000894

Short ribs

0000773

Spina bifida

0002414

Strabismus

Cross-eyed

Squint

Squint eyes

[ more ]

0000486

Subcutaneous nodule

Firm lump under the skin

Growth of abnormal tissue under the skin

[ more ]

0001482

5%-29% of people have these symptoms

Abdominal pain

Pain in stomach

Stomach pain

[ more ]

0002027

Abnormal adipose tissue morphology

Abnormality of adipose tissue

Abnormality of fat tissue

Abnormality of fatty tissue

[ more ]

0009124

Abnormality of the mediastinum

0045026

Abnormality of the pulmonary vasculature

Abnormality of the lung blood vessels

0004930

Acute hepatic failure

Acute liver failure

0006554

Aplasia/Hypoplasia of the lungs

Absent/small lungs

Absent/underdeveloped lungs

[ more ]

0006703

Congenital diaphragmatic hernia

0000776

Diagnosis

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

Related diseases

Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.

Conditions with similar signs and symptoms from Orphanet
Differential diagnoses should include microphtalmia with linear skin defects (MLS) and incontinentia pigmenti (IP), as well as oculocerebrocutaneous syndrome and Rothmund-Tompson syndrome. Visit the Orphanet disease page for more information.

Organizations

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

National Foundation for Ectodermal Dysplasias
6 Executive Drive
Suite 2
Fairview Heights, IL 62258-1360
Telephone: +1-618-566-2020
Fax: +1-618-566-4718
E-mail: [email protected]
Website: https://www.nfed.org/
The Ectodermal Dysplasia Society
Unit 1 Maida Vale Business Centre
Leckhampton
Cheltenham
Gloucestershire GL53 7ER
United Kingdom
Telephone: +44 (0) 1242 261332
E-mail: [email protected]
Website: https://edsociety.co.uk/

Learn more

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

DermNet NZ is an online resource about skin diseases developed by the New Zealand Dermatological Society Incorporated. DermNet NZ provides information about this condition.
Genetics Home Reference (GHR) contains information on Focal dermal hypoplasia. This website is maintained by the National Library of Medicine.
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

GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
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 Focal dermal hypoplasia. Click on the link to view a sample search on this topic.

References

Focal dermal hypoplasia. Genetics Home Reference. July 2014; https://ghr.nlm.nih.gov/condition/focal-dermal-hypoplasia.
Sutton, V Reid and Van den Veyver, Ignatia. Focal Dermal Hypoplasia. GeneReviews. April, 2013; https://www.ncbi.nlm.nih.gov/books/NBK1543/. Accessed 1/29/2016.
Focal Dermal Hypoplasia. Genetics Home Reference. July, 2014; https://ghr.nlm.nih.gov/condition/focal-dermal-hypoplasia. Accessed 1/29/2016.

Rare Pulmonology News

Rare Pulmonology News

Rare Pulmonology News

Neonatal

Q82.8

Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.

Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.

X-linked dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.

X-linked recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.

Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.

Not applicable

Other names (AKA)

Categories

Summary

Symptoms

Diagnosis

Testing Resources

Related diseases

Organizations

Organizations Supporting this Disease

Learn more

Where to Start

In-Depth Information

References

X-linked
dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.

X-linked
recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.