Genetic testing may be available for mutations in the FGDY1 gene. Genetic counseling is indicated for individuals or families who may carry this condition, as there are overlapping features with fetal alcohol syndrome.

Other examinations or tests can help with diagnosis. These can include:

detailed family history

- conducting a detailed physical examination to document morphological features

- testing for genetic defect in FGDY1

- x-rays can identify skeletal abnormalities

- echo cardiogram can screen for heart abnormalities

- CT scan of the brain for cystic development

- X-ray of the teeth

- Ultrasound of abdomen to identify undescended testis

A 2007 study followed 112 individuals for a mean of 12 years (mean age 25.3, range 12–71). No patient died during follow-up, but several required medical interventions. The mean final heights were 167 and 153 cm for men and women, respectively, which is approximately 2 standard deviations below normal.

First trimester ultrasound of noonan syndrome reveals nuchal oedema / cystic hygroma almost same as seen in Turner syndrome. Follow up scans may shows clinical features that already described above.

A study shows this disease is also associated with hepato splenomegaly with renal anomalies including malrotation and solitary kidney. A rare incidence of choledochal cyst is also reported as well.

The diagnosis of this syndrome can be made on clinical examination and perinatal autopsy.

Koenig and Spranger (1986) noted that eye lesions are apparently nonobligatory components of the syndrome. The diagnosis of Fraser syndrome should be entertained in patients with a combination of acrofacial and urogenital malformations with or without cryptophthalmos. Thomas et al. (1986) also emphasized the occurrence of the cryptophthalmos syndrome without cryptophthalmos and proposed diagnostic criteria for Fraser syndrome. Major criteria consisted of cryptophthalmos, syndactyly, abnormal genitalia, and positive family history. Minor criteria were congenital malformation of the nose, ears, or larynx, cleft lip and/or palate, skeletal defects, umbilical hernia, renal agenesis, and mental retardation. Diagnosis was based on the presence of at least 2 major and 1 minor criteria, or 1 major and 4 minor criteria.

Boyd et al. (1988) suggested that prenatal diagnosis by ultrasound examination of eyes, digits, and kidneys should detect the severe form of the syndrome. Serville et al. (1989) demonstrated the feasibility of ultrasonographic diagnosis of the Fraser syndrome at 18 weeks' gestation. They suggested that the diagnosis could be made if 2 of the following signs are present: obstructive uropathy, microphthalmia, syndactyly, and oligohydramnios. Schauer et al. (1990) made the diagnosis at 18.5 weeks' gestation on the basis of sonography. Both the female fetus and the phenotypically normal father had a chromosome anomaly: inv(9)(p11q21). An earlier born infant had Fraser syndrome and the same chromosome 9 inversion.

Van Haelst et al. (2007) provided a revision of the diagnostic criteria for Fraser syndrome according to Thomas et al. (1986) through the addition of airway tract and urinary tract anomalies to the major criteria and removal of mental retardation and clefting as criteria. Major criteria included syndactyly, cryptophthalmos spectrum, urinary tract abnormalities, ambiguous genitalia, laryngeal and tracheal anomalies, and positive family history. Minor criteria included anorectal defects, dysplastic ears, skull ossification defects, umbilical abnormalities, and nasal anomalies. Cleft lip and/or palate, cardiac malformations, musculoskeletal anomalies, and mental retardation were considered uncommon. Van Haelst et al. (2007) suggested that the diagnosis of Fraser syndrome can be made if either 3 major criteria, or 2 major and 2 minor criteria, or 1 major and 3 minor criteria are present in a patient.

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 diagnosis is usually based on clinical features present at birth.

Ultrasound in the second trimester may show abnormalities associates with NLS, including polyhydramnios, intrauterine growth restriction, microcephaly, proptosis and decreased fetal motility.

The prognosis is poor; affected individuals are either stillborn or die shortly after birth. The longest survival reported in literature is of 134 days.

This syndrome is transmitted as an autosomal recessive disorder and there is a risk for recurrence of 25% in future pregnancies.

The diagnosis CFND is established only after the presence of a mutation in the EFNB1 gene has been determined. Physical manifestations are not necessarily part of the diagnostic criteria, but can help guide in the right direction. This is due to the large heterogeneity between patients regarding phenotypic expression.

20% of the patients that present with CFND-like characteristics do not display a mutation in the EFNB1 gene. The group of patients diagnosed with CFND is thus often overestimated. However, it is important to distinguish this population from CFND for research purposes. On the other hand, especially in males, it is possible that someone is a carrier of the EFNB1 gene mutation yet does not present with any physical manifestations. Screening for the presence of an EFNB1 mutation is thus the most reliable method to establish the diagnosis CFND.

Genetic counseling or prenatal screening may be advised if there is a reason to suspect the presence of an EFNB1 gene mutation. Prenatal screening may be done by performing an ultrasound, where can be searched specifically for hypertelorism or a bifid nasal tip. However, this is quite difficult as facial involvement may not be obvious at such an early age, especially in cases with mild phenotypic presentation. The most definitive way to prove the presence of CFND is done by genetic testing, through amniocentesis and chorionic villus sampling. This however carries a greater risk of premature termination of the pregnancy.

Diagnosis is usually based on clinical findings, although fetal chromosome testing will show trisomy 13. While many of the physical findings are similar to Edwards syndrome there are a few unique traits, such as polydactyly. However, unlike Edwards syndrome and Down syndrome, the quad screen does not provide a reliable means of screening for this disorder. This is due to the variability of the results seen in fetuses with Patau.

Genetic testing for CHARGE syndrome involves specific genetic testing for the CHD7 gene. The test is available at most major genetic testing laboratories. Insurance companies sometimes do not pay for such genetic tests, though this is changing rapidly as genetic testing is becoming standard across all aspects of medicine. CHARGE syndrome is a clinical diagnosis, which means genetic testing is not required in order to make the diagnosis. Rather, the diagnosis can be made based on clinical features alone.

Once the diagnosis is made based on clinical signs, it is important to investigate other body systems that may be involved. For example, if the diagnosis is made based on the abnormal appearance of the ears and developmental delay, it is important to check the child's hearing, vision, heart, nose, and urogenital system. Ideally, every child newly diagnosed with CHARGE syndrome should have a complete evaluation by an ENT specialist, audiologist, ophthalmologist, pediatric cardiologist, developmental therapist, and pediatric urologist.

Some people may have some mental slowness, but children with this condition often have good social skills. Some males may have problems with fertility.

Though only definitively diagnosable by genetic sequence testing, including a G band analysis, ATR-16 syndrome may be diagnosed from its constellation of symptoms. It must be distinguished from ATR-X syndrome, a very similar disease caused by a mutation on the X chromosome, and cases of alpha-thalassemia that co-occur with intellectual disabilities with no underlying genetic relationship.

The diagnosis of Wilson–Turner syndrome is based upon a clinical evaluation, a detailed patient history, and identification of characteristic features. Molecular genetic testing for mutations in the HDAC8 gene is now available to confirm the diagnosis.

Treatments for ATR-16 syndrome depend on the symptoms experienced by any individual. Alpha thalassemia is usually self-limiting, but in some cases may require a blood transfusion or chelating treatment.

The diagnosis of harlequin-type ichthyosis relies on both physical examination and certain laboratory tests.

Physical assessment at birth is vital for the initial diagnosis of harlequin ichthyosis. Physical examination reveals characteristic symptoms of the condition especially the abnormalities in the skin surface of newborns. Abnormal findings in physical assessments usually result in employing other diagnostic tests to ascertain the diagnosis.

Genetic testing is the most specific diagnostic test for harlequin ichthyosis. This test reveals a loss of function mutation on the ABCA12 gene. This gene is important in the regulation of protein synthesis for the development of the skin layer. Mutations in the gene may cause impaired transport of lipids in the skin layer and may also lead to shrunken versions of the proteins responsible for skin development. Less severe mutations result in a collodion membrane and congenital ichthyosiform erythroderma-like presentation. ABCA12 is an ATP binding cassette (ABC) transporter, and is a member of a large family of proteins that hydrolyze ATP to transport cargo across membranes. ABCA12 is thought to be a lipid transporter in keratinocytes necessary for lipid transport into lamellar granules during the formation of the lipid barrier.

Biopsy of skin may be done to assess the histologic characteristics of the cells. Histological findings usually reveal hyperkeratotic skin cells, which leads to a thick, white and hard skin layer.

The Wilson–Turner syndrome is characterized by mild to moderate range of intellectual disability, obesity, tapered fingers, and mood swings. Males also suffer from gynecomastia and hypogonadism. In order to be diagnosed with Wilson-Turner Syndrome, male patients must suffer from intellectual disability, obesity, and gynecomastia. Females do not necessarily have to have noticeable phenotype but can be diagnosed with this disorder by studying her family history and identifying others with the disorder. It has been noted that children with Wilson-Turner Syndrome will display speech development delay and excessive drooling. Males can be confirmed by testing androgen levels. Female carriers will show silencing of the gene a complex X inactivation.

This disorder is caused by an abnormality of the TBCE gene, the locus for which is on Chromosome 1q42.3. The locus is a 230 kb region of gene with identified deletions and mutations in affected individuals. There are rare cases of the disorder not being due to a TBCE gene abnormality.

Vestronidase alfa-vjbk (Mepsevii) is the only drug approved by U.S. Food and Drug Administration for the treatment of pediatric and adult patients.

Other features include:

- Stunting

- Small hands and feet with long, tapering fingers and clinodactyly

- Dental anomalies in the form of malalignment and malocclusion

In another study of six patients, the patients were investigated further. They were found to have low levels of IGF-1 and markedly retarded bone age.

Zimmermann–Laband syndrome (ZLS), also known as Laband–Zimmermann syndrome, and Laband's syndrome, is an extremely rare autosomal dominant congenital disorder.

Nablus mask-like facial syndrome is a microdeletion syndrome triggered by a deletion at chromosome 8 q22.1 that causes a mask-like facial appearance in those affected.

It is characterized by a narrowing of the eyes, tight, glistening facial skin, and a flat, broad nose. Other features of the syndrome include malformed ears, unusual hair patterns on the scalp, bent fingers and toes and joint deformities in the hands and feet, unusual teeth, mild developmental delay, cryptorchidism, and a generally happy disposition. It is a rare genetic disorder by inheritance found in Palestinian people named after Nablus city in the West Bank. It is part of many new genetic disorders of newborns that is increasing exponentially in Arabs in recent years as reported by Centre for Arab Genomic Studies in Dubai.

Symptoms include gingival fibromatosis, associated with hypoplasia of the distal phalanges, nail dysplasia, joint hypermobility, and sometimes hepatosplenomegaly. The nose and pinnae are usually large and poorly developed, which gives the individuals with the syndrome abnormal facial characteristics. Mental retardation may also occur. Both males and females are equally affected. Gingival fibromatosis is usually present at birth or appears short after. The term Zimmermann–Laband was coined by Carl Jacob Witkop in 1971.

The actual incidence of this disease is not known, but only 243 cases have been reported in the scientific literature, suggesting an incidence of on the order of one affected person in ten million people.

The incidence of Fraser syndrome is 0.043 per 10,000 live born infants and 1.1 in 10,000 stillbirths, making it a rare syndrome.