In many cases, MHA requires no treatment. However, in extreme cases, blood platelet transfusions may be necessary

People may be diagnosed after prolonged and/or recurring bleeding episodes. Children and adults may also be diagnosed after profuse bleeding after a trauma or tooth extraction. Ultimately, a laboratory diagnosis is usually required. This would utilize platelet aggregation studies and flow cytometry.

Elevated IgE is the hallmark of HIES. An IgE level greater than 2,000 IU/mL is often considered diagnostic. However, patients younger than 6 months of age may have very low to non-detectable IgE levels. Eosinophilia is also a common finding with greater than 90% of patients having eosinophil elevations greater than two standard deviations above the normal mean. Genetic testing is available for "STAT3" (Job's Syndrome), "DOCK8 (DOCK8 Immunodeficiency or DIDS)", "PGM3" (PGM3 deficiency), "SPINK5" (Netherton Syndrome - NTS), and "TYK2" genetic defects.

Though it is only definitively diagnosed by a genetic test, autosomal dominant porencephaly type I can be suspected if the disease is known to run in the family or if someone shows symptoms. CT scanning or MRI may be useful in indicating a diagnosis. COL4A1 may be mutated in other diseases that need to be distinguished, including brain small vessel disease with hemorrhage and HANAC syndrome. CADASIL syndrome is caused by a mutation in a different gene, but may cause similar symptoms. Sporadic porencephaly is another disorder that can appear similar.

There has been no general recommendation for treatment of patients with Giant Platelet Disorders, as there are many different specific classifications to further categorize this disorder which each need differing treatments. Platelet transfusion is the main treatment for people presenting with bleeding symptoms. There have been experiments with DDAVP (1-deamino-8-arginine vasopressin) and splenectomy on people with Giant platelet disorders with mixed results, making this type of treatment contentious.

Most patients with hyper IgE syndrome are treated with long-term antibiotic therapy to prevent staphylococcal infections. Good skin care is also important in patients with hyper IgE syndrome. High-dose intravenous gamma-globulin has also been suggested for the treatment of severe eczema in patients with HIES and atopic dermatitis.

Medical diagnosis is required. Clinical tests can be performed, as well as molecular genetic testing. The available tests include:

Sequence analysis of the entire coding region

- Severe achondroplasia with developmental delay and acanthosis nigricans (SADDAN) - Sanger Sequencing: Diagnosis, Mutation Confirmation, Pre-symptomatic, Risk Assessment, Screening

- Craniosynostosis: Diagnosis

- Invitae FGFR3-Related Disorders Test: Pre-symptomatic, Diagnosis, Therapeutic management

Mutation scanning of select exons

- Skeletal Dysplasia Panel: Diagnosis, Prognostic

Sequence analysis of select exons

- Severe Achondroplasia with Developmental Delay and Acanthosis Nigricans (SADDAN, FGFR3): Diagnosis, Mutation Confirmation, Risk Assessment

- Severe Achondroplasia, Developmental Delay, Acanthosis Nigricans: Diagnosis, Mutation Confirmation

Deletion/duplication analysis

- Invitae FGFR3-Related Disorders Test: Pre-symptomatic, Diagnosis, Therapeutic management

Life with SADDAN is manageable, although therapy, surgery, and lifelong doctor surveillance may be required.

Pachyonychia congenita may be divided into these types:

- Pachyonychia congenita type I (also known as "Jadassohn–Lewandowsky syndrome") is an autosomal dominant keratoderma that principally involves the plantar surfaces, but also with nails changes that may be evident at birth, but more commonly develop within the first few months of life.

- Pachyonychia congenita type II (also known as "Jackson–Lawler pachyonychia congenita" and "Jackson–Sertoli syndrome") is an autosomal dominant keratoderma presenting with a limited focal plantar keratoderma that may be very minor, with nails changes that may be evident at birth, but more commonly develop within the first few months of life.

Treatment for autosomal dominant porencephaly type I is based on the symptoms that an individual is experiencing - for example, treatment of seizures with anticonvulsants. It is particularly important for individuals with this disorder and hypertension to control their blood pressure, as they are at higher risk of stroke. Other stroke prevention treatments include avoiding anticoagulants, smoking, and situations that may lead to head trauma.

May–Hegglin anomaly (MHA), also known as Döhle leukocyte inclusions with giant platelets and macrothrombocytopenia with leukocyte inclusions, is a rare genetic disorder of the blood platelets that causes them to be abnormally large.

The differential diagnosis is quite extensive and includes

- Buschke–Fischer–Brauer disease

- Curth–Macklin ichthyosis

- Gamborg Nielsen syndrome

- Greither disease

- Haber syndrome

- Hereditary punctate palmoplantar keratoderma

- Jadassohn–Lewandowsky syndrome

- Keratosis follicularis spinulosa decalvans

- Keratosis linearis with ichthyosis congenital and sclerosing keratoderma syndrome

- Meleda disease

- Mucosa hyperkeratosis syndrome

- Naegeli–Franceschetti–Jadassohn syndrome

- Naxos disease

- Olmsted syndrome

- Palmoplantar keratoderma and leukokeratosis anogenitalis

- Pandysautonomia

- Papillomatosis of Gougerot and Carteaud

- Papillon–Lefèvre syndrome

- Punctate porokeratotic keratoderma

- Richner–Hanhart syndrome

- Schöpf–Schulz–Passarge syndrome

- Unna Thost disease

- Vohwinkel syndrome

- Wong's dermatomyositis

Howel–Evans syndrome is an extremely rare condition involving thickening of the skin in the palms of the hands and the soles of the feet (hyperkeratosis). This familial disease is associated with a high lifetime risk of esophageal cancer. For this reason, it is sometimes known as tylosis with oesophageal cancer (TOC).

The condition is inherited in an autosomal dominant manner, and it has been linked to a mutation in the "RHBDF2" gene. It was first described in 1958.

Definitive diagnosis of FTDP-17 requires a combination of characteristic clinical and pathological features and molecular genetic analysis. Genetic counseling should be offered to affected and at-risk individuals; for most subtypes, penetrance is incomplete.

Fechtner syndrome is a variant of Alport syndrome characterized by leukocyte inclusions, macrothrombocytopenia, thrombocytopenia, nephritis, and sensorineural hearing loss. Some patients may also develop cataracts.

Due to the wide range of genetic disorders that are presently known, diagnosis of a genetic disorder is widely varied and dependent of the disorder. Most genetic disorders are diagnosed at birth or during early childhood, however some, such as Huntington's disease, can escape detection until the patient is well into adulthood.

The basic aspects of a genetic disorder rests on the inheritance of genetic material. With an in depth family history, it is possible to anticipate possible disorders in children which direct medical professionals to specific tests depending on the disorder and allow parents the chance to prepare for potential lifestyle changes, anticipate the possibility of stillbirth, or contemplate termination. Prenatal diagnosis can detect the presence of characteristic abnormalities in fetal development through ultrasound, or detect the presence of characteristic substances via invasive procedures which involve inserting probes or needles into the uterus such as in amniocentesis.

Prognosis strongly depends on which subtype of disease it is. Some are deadly in infancy but most are late onset and mostly manageable.

Brain MRI shows vermis atrophy or hypoplasic. Cerebral and cerebellar atrophy with white matter changes in some cases.

Not all genetic disorders directly result in death, however there are no known cures for genetic disorders. Many genetic disorders affect stages of development such as Down syndrome. While others result in purely physical symptoms such as muscular dystrophy. Other disorders, such as Huntington's disease show no signs until adulthood. During the active time of a genetic disorder, patients mostly rely on maintaining or slowing the degradation of quality of life and maintain patient autonomy. This includes physical therapy, pain management, and may include a selection of alternative medicine programs.

Usually, a common form of treatment for the condition is a type of hand cream which moisturises the hard skin. However, currently the condition is incurable.

The diagnosis is based on the following clinical findings:

- microcephaly

- clinodactyly and shortness of index and little fingers

- syndactyly of 2nd & 3rd and 4th & 5th toe

- short palpebral fissures

- esophageal and/or duodenal atresia

Ultrasound remains as one of the only effective ways of prenatally diagnosing Larsen syndrome. Prenatal diagnosis is extremely important, as it can help families prepare for the arrival of an infant with several defects. Ultrasound can capture prenatal images of multiple joint dislocations, abnormal positioning of legs and knees, depressed nasal bridge, prominent forehead, and club feet. These symptoms are all associated with Larsen syndrome, so they can be used to confirm that a fetus has the disorder.

Pachyonychia congenita follows an autosomal dominant pattern of inheritance, which means the defective gene is located on an autosome, and only one copy of the gene is required to inherit the disorder from a parent who has the disorder. On average, 50% of the offspring of an affected person will inherit the disorder, regardless of gender.

Occasionally, however, a solitary case can emerge in a family with no prior history of the disorder due to the occurrence of a new mutation (often referred to as a sporadic or spontaneous mutation).

Blau Syndrome is an autosomal dominant genetic inflammatory disorder which affects the skin, eyes, and joints. It is caused by a mutation in the NOD2 (CARD15) gene. Symptoms usually begin before the age of 4, and the disease manifests as early onset cutaneous sarcoidosis, granulomatous arthritis, and uveitis.

Sorsby's fundus dystrophy (SFD) is a very rare genetic disorder characterized by the loss of central vision. It was first described by Sorsby and Mason in 1949.

The diagnosis of Muenke syndrome is suspected bases on abnormal skull shape and a diagnosis of coronal craniosynostosis. In 2006, Agochukwu and her colleagues concluded that “A distinct Muenke syndrome phenotype includes: uni or bilateral coronal synostosis, midface hypoplasia, broad toes, and brachydactyly.” Due to phenotypic overlap and/or mild phenotypes, clinical differentiation of this syndrome may be difficult. The suspected diagnosis is confirmed by a blood test to check for gene mutation. To establish the extent of disease in an individual diagnosed with Muenke syndrome, various evaluations are recommended.