There are very few ways to test a patient for HGF. Currently, the most common way to diagnose a patient is by means of a physical evaluation. The physician can make a physical evaluation of the patient and send them to a dentist or better yet a specialist like a periodontist to evaluate signs of gingival overgrowth, quality of gingiva, inflammation, mechanical difficulties of the mouth, tooth conditions, and any sort of discomfort.

Aside from obvious physical symptoms seen in a physical evaluation, molecular tests can be run to check if there is a mutation in the SOS1 gene to confirm the diagnosis. If there is indeed a mutation in this gene coupled with the typical physical symptoms, then it is quite probable that a patient suffers from this disease. Also, looking at family history is also becoming more prominent in aiding to diagnose the patient. Otherwise, researchers are working to find new and better ways to test for the presence of HGF.

The symptoms would appear at birth or shortly after birth. The combination of physical symptoms on the child would suggest they have CHILD syndrome. A skin sample examined under a microscope would suggest the characteristics of the syndrome and an X-Ray of the trunk, arms, and legs would help to detect underdeveloped bones. A CT scan would help detect problems of the internal organs.

Since this condition is generally agreed upon to be hereditary, nothing can be done to prevent HGF. However, in some cases where it can develop as a result of rare multi-system syndromes, such as: Zimmerman-Laband, Jones, Ramon Syndrome, Rutherford Syndrome, Juvenile Hyaline Fibromatosis, Systemic Infantile Hyalinosis, and Mannosidosis, it is best for one to simply monitors the possible progression for HGF with regular dental check-ups.

If the patient's disease is treated by means of surgery, it is recommended that the patient undergoes post-surgical therapies for maintenance and periodic monitoring of gums for the sake of the possibility of re-occurrence of HGF.

The diagnosis is based on the combination of the symptoms. Generally, people are diagnosed with yellow nail syndrome if they have two or three of the three classical symptoms (yellow nails, lymphedema and lung problems). The nail changes are considered essential for the diagnosis, but they can be subtle.

Pulmonary function testing can show obstruction of the airways. People with pleural effusions may show evidence of restriction in lung volumes due to the fluid. Analysis of the fluid in pleural effusions generally shows high levels of protein but low levels of cholesterol and lactate dehydrogenase, but about 30% of effusions are chylous (chylothorax) in that they have the characteristics of lymph.

A lymphogram may be performed in people with lymphedema. This can show both under developed (hypoplastic) lymphatic ducts and dilated ducts. Dye may be found in the skin months after the initial test. Scintigraphy of lymph flow (lymphoscintigraphy) shows delays in drainage of lymph (sometimes asymmetrically), although this test can also be normal.

There is currently no treatment for CHILD syndrome so any treatment would target the symptoms currently present. Emoillents like Lac-Hydran (ammonium lactate) and Ureaphil (urea) are used to treat scaly patches on the skin. A pediatric orthopedic surgeon can evaluate any underdevelopment in the bones and treat them if necessary.

There is a compound that is a topical liquid that can calm lesions down on older adults and make them go away on younger children. The mixture was made by Dr. Amy Paller at Children's Hospital. It is mixed as follows: to make 250 ml: Grind up lovastatin tablets 5g (10-20-40-80 mg); mix with cholesterol NF powder (NDC# 51927-1203-00, PCCA) 5g; mix with preserved water while mixing (eventually mixing for 1/2 hour with electronic mortar and pestle) to bring to full volume with preserved water. 8 oz

Treatment for NPS varies depending on the symptoms observed.

- Perform screening for renal disease and glaucoma, surgery, intensive physiotherapy, or genetic counseling.

- ACE inhibitors are taken to treat proteinuria and hypertension in NPS patients.

- Dialysis and renal transplant.

- Physical therapy, bracing and analgesics for joint pain.

- Other surgery treatments such as patella realignment, joint replacement, and the cutting away of the head of radius.

Autosomal recessive inheritance is the most likely, but sporadic mutations and autosomal dominant cases may also occur.

This syndrome has been associated with mutations in the ARID1B gene.

Mutations in SOX11 are associated to this syndrome.

The diagnosis is generally based on the presence of major and at least one minor clinical sign and can be confirmed by molecular genetic testing of the causative genes. Recent studies revealed that fifth finger nail/distal phalanx hypoplasia or aplasia is not a mandatory finding.

People with yellow nail syndrome have been found to have a moderately reduced lifespan compared to people without the condition.

Microlissencephaly can be diagnosed by prenatal MRI. MRI is better than ultrasound when it comes to detecting microlissencephaly or MSGP prenatally.

The ideal time for proper prenatal diagnosis is between the 34th and 35th gestational week which is the time when the secondary gyration normally terminates. In microlissencephaly cases, the primary sulci would be unusually wide and flat while secondary sulci would be missing.

At birth, lissencephaly with a head circumference of less than minus three standard deviations (< –3 SD) is considered microlissencephaly.

Although genetic diagnosis in patients with MLIS is challenging, exome sequencing has been suggested to be a powerful diagnostic tool.

MDM is most common on the Dalmatian island of Mljet (or "Meleda"), thought to be because of a founder effect. It is of autosomal recessive inheritance. It may be caused by a mutation on the "SLURP1" gene, located on chromosome 8.

Arts syndrome should be included in the differential diagnosis of infantile hypotonia and weakness aggravated by recurrent infection with a family history of X-linked inheritance. Sequence analysis of PRPS1, the only gene associated with Arts syndrome, has detected mutations in both kindreds reported to date. Arts syndrome patients were also found to have reduced levels of hypoxanthine levels in urine and uric acid levels in the serum. In vitro, PRS-1 activity was reduced in erythrocytes and fibroblasts.

Tooth and nail syndrome (also known as "Hypodontia with nail dysgenesis," and "Witkop syndrome") is a rare disorder, first described in 1965, characterized by nails that are thin, small, and friable, and which may show koilonychia at birth.

It is associated with "MSX1".

Meleda disease (MDM) or "mal de Meleda", also called Mljet disease, keratosis palmoplantaris and transgradiens of Siemens, (also known as "Acral keratoderma," "Mutilating palmoplantar keratoderma of the Gamborg-Nielsen type," "Palmoplantar ectodermal dysplasia type VIII", and "Palmoplantar keratoderma of the Norrbotten type") is an extremely rare autosomal recessive congenital skin disorder in which dry, thick patches of skin develop on the soles of the hands and feet, a condition known as palmoplantar hyperkeratosis.

Lelis syndrome it is a genetic disorder, a rare condition with dermatological and dental findings characterized by the association of ectodermal dysplasia (hypotrichosis and hypohidrosis) with acanthosis nigricans. Other clinical features may include palmoplantar hyperkeratosis, nail dystrophy, intellectual deficit, disturbances of skin pigmentation (perioral and periorbital hyperpigmentation, vitiligo, and perinevic leukoderma) and hypodontia. Transmission is autosomal recessive.

A doctor will take a thorough medical history, and may take blood tests as well as examining liver and kidney function. Improvements have also been reported from treating malnutrition associated with zinc deficiency and other minerals. Intracellular (red blood cell) assays are more sensitive than tests for plasma levels.

Microlissencephaly is considered a more severe form than microcephaly with simplified gyral pattern. Microlissencephaly is characterized by a smooth cortical surface (absent sulci and gyri) with a thickened cortex (> 3 mm) and is usually associated with other congenital anomalies. Microcephaly with a simplified gyral pattern has too few sulci and normal cortical thickness (3 mm) and is usually an isolated anomaly.

Sabinas brittle hair syndrome is inherited as an autosomal recessive genetic trait.

In a study by Howell et al. patients were located and studied by means of complete histories and physical examinations, analyses of serum trace metals, ceruloplasmin concentration, urine and serum amino acids, and routine metabolic urine screens. In addition, serum and urine luteinizing hormone (LH) and follicle-stimulating hormone (FSH) values were determined, and were interpreted in conjunction with total plasma estrogen, estradiol, and testosterone levels. Close examination demonstrated the scalp hairs were very brittle, coarse, wiry in texture, and broke off quite easily with mechanical trauma such as combing and brushing. Some hairs could be visualized in their follicles, which were broken off at the skin line. Most patients had accompanying hyperkeratosis (thickening of the skin) of moderate degree on exposed surfaces. Maxillary hypoplasia (midfacial retrusion) was significant in many patients. The brittle, short hair, reduced eyelashes, crowded teeth, and dull appearance created a characteristic facial appearance. Post-pubertal patients had development of secondary sexual characteristics consistent with their age, except for sparse pubic escutcheons. All cases studied demonstrated some degree of mental deficiency; I.Q.'s ranged between 50–60. A deficiency in eye–hand coordination was also noted.

Fibrochondrogenesis is quite rare. A 1996 study from Spain determined a national minimal prevalence for the disorder at 8 cases out of 1,158,067 live births.

A United Arab Emirates (UAE) University report, from early 2003, evaluated the results of a 5-year study on the occurrence of a broad range of osteochondrodysplasias. Out of 38,048 newborns in Al Ain, over the course of the study period, fibrochondrogenesis was found to be the most common of the recessive forms of osteochondrodysplasia, with a prevalence ratio of 1.05:10,000 births.

While these results represented the most common occurrence within the group studied, they do not dispute the rarity of fibrochondrogenesis. The study also included the high rate of consanguinous marriages as a prevailing factor for these disorders, as well as the extremely low rate of diagnosis-related pregnancy terminations throughout the region.

Some recommend avulsion of the nail plate with surgical destruction of the nail matrix with phenol or the carbon dioxide laser, if the blood supply is good.

A review from 2000 stated that life expectancy was reduced because of a tendency to develop cancer relatively early as well as deaths due to infections related to immunodeficiency.

DC is associated with shorter life expectancy, but many live to at least age 60.

Recent research has used induced pluripotent stem cells to study disease mechanisms in humans, and discovered that the reprogramming of somatic cells restores telomere elongation in dyskeratosis congenita (DKC) cells despite the genetic lesions that affect telomerase. The reprogrammed DKC cells were able to overcome a critical limitation in TERC levels and restored function (telomere maintenance and self-renewal). Therapeutically, methods aimed at increasing TERC expression could prove beneficial in DKC.

Pure hair-nail type ectodermal dysplasia is a genetic mutation in the "hair matrix and cuticle keratin KRTHB5 gene" that causes ectodermal dysplasia of hair and nail type. Manifestations of this disorder include onychodystrophy and severe hypotrichosis. It represents as an autosomal dominant trait.

Coffin–Siris Syndrome is a rare genetic disorder that causes developmental delays and absent fifth finger and toe nails.

There had been 31 reported cases by 1991. The numbers of occurrence since then has grown and is reported to be around 80.

The differential includes Nicolaides–Baraitser syndrome.

The fibrocartilaginous effects of fibrochondrogenesis on chondrocytes has shown potential as a means to produce therapeutic cellular biomaterials via tissue engineering and manipulation of stem cells, specifically human embryonic stem cells.

Utilization of these cells as curative cartilage replacement materials on the cellular level has shown promise, with beneficial applications including the repair and healing of damaged knee menisci and synovial joints; temporomandibular joints, and vertebra.