X-ray and neuroimaging studies may be helpful in confirming a diagnosis of Coffin–Lowry syndrome. Decreased ribosomal S6 kinase activity in cultured fibroblast or transformed lymphoblast cells from a male indicates Coffin–Lowry syndrome. Studies of enzyme activity can not be used to diagnose an affected female.

Molecular genetic testing on a blood specimen or cells from a cheek swab is available to identify mutations in the RSK2 gene. This testing can be used to confirm but not rule out the diagnosis of Coffin–Lowry syndrome because not all affected individuals have a detectable mutation.

Screening generally only takes place among those displaying several of the symptoms of ABCD, but a study on a large group of institutionalized deaf people in Columbia revealed that 5.38% of them were Waardenburg patients. Because of its rarity, none of the patients were diagnosed with ABCD (Waardenburg Type IV). Nothing can be done to prevent the disease.

MORM syndrome is a genetic disorder obtained through inheritance. The main method for testing individuals showing symptoms of MORM syndrome is sequence analysis of the entire coding region. When performing a sequence analysis of the entire coding region the gene INNP5E is targeted. Sequence analysis is the biotechnological process in which the structure and sequence of DNA, RNA, or protein sequence is determined through the use of technology. The sequence can then be analyzed to determine mutations or abnormalities in that particular region. When testing for MORM syndrome, sequence analysis of the region of the genome which contains the gene INPP5E is targeted and examined to look for mutations.

Carrier testing for Roberts syndrome requires prior identification of the disease-causing mutation in the family. Carriers for the disorder are heterozygotes due to the autosomal recessive nature of the disease. Carriers are also not at risk for contracting Roberts syndrome themselves. A prenatal diagnosis of Roberts syndrome requires an ultrasound examination paired with cytogenetic testing or prior identification of the disease-causing ESCO2 mutations in the family.

The occurrence of WS has been reported to be one in 45,000 in Europe. The diagnosis can be made prenatally by ultrasound due to the phenotype displaying pigmentary disturbances, facial abnormalities, and other developmental defects. After birth, the diagnosis is initially made symptomatically and can be confirmed through genetic testing. If the diagnosis is not made early enough, complications can arise from

Hirschsprung's disease.

Kabuki syndrome can be diagnosed using whole exome or whole genome sequencing. Some patients who were initially clinically diagnosed with Kabuki syndrome were actually found to have Wiedemann-Steiner syndrome.

This includes Ataxia-telegiectasia, Chédiak-Higashi syndrome, DiGeorge syndrome, Griscelli syndrome and Marinesco-Sjogren syndrome.

Most individuals with this condition do not survive beyond childhood. Individuals with MDS usually die in infancy and therefore do not live to the age where they can reproduce and transmit MDS to their offspring.

The duplication involved in PTLS is usually large enough to be detected through G-banding alone, though there is a high false negative rate. To ascertain the diagnosis when karyotyping results are unclear or negative, more sophisticated techniques such as subtelomeric fluorescent in-situ hybridization analysis and array comparative genomic hybridization (aCGH) may be used.

While no cure for MDS is available yet, many complications associated with this condition can be treated, and a great deal can be done to support or compensate for functional disabilities. Because of the diversity of the symptoms, it can be necessary to see a number of different specialists and undergo various examinations, including:

- Developmental evaluation

- Cardiologists evaluation

- Otolaryngology

- Treatment of seizures

- Urologic evaluation

- Genetic counseling-balanced chromosomal translocation should be excluded in a parents with an affected child are planning another pregnancy, so parents with affected children should visit a genetic counselor.

The diagnostic work up usually includes and MRI of the brain, an EEG, ophthalmic examination and a cardiac ECHO.

Muscle biopsy - which is not commonly done - may show storage of abnormal material and secondary mitochondrial abnormalities in skeletal muscle. Other features that may be seen on muscle biopsy include variability in fibre size, increase in internal and centralized nuclei, type 1 fibre hypotrophy with normally sized type 2 fibres, increased glycogen storage and variable vacuoles on light microscopy

The diagnosis is confirmed by sequencing of the EPG5.

Since Duane-radial ray syndrome is a genetic disorder, a genetic test would be performed. One test that can be used is the SALL4 sequence analysis that is used to detect if SALL4 is present. If there is no pathogenic variant observed, a deletion/duplication analysis can be ordered following the SALL4 sequence analysis. As an alternative, another genetic test called a multi-gene panel can be ordered to detect SALL4 and any other genes of interest. The methods used for this panel vary depending on the laboratory.

Initially, the clinical presentation of SDS may appear similar to cystic fibrosis. However, CF can be excluded with a normal chloride in sweat test but faecal elastase as a marker of pancreatic function will be reduced. The variation, intermittent nature, and potential for long-term improvement of some clinical features make this syndrome difficult to diagnose. SDS may present with either malabsorption, or hematological problems. Rarely, SDS may present with skeletal defects, including severe rib cage abnormalities that lead to difficulty in breathing. Diagnosis is generally based on evidence of exocrine pancreatic dysfunction and neutropenia. Skeletal abnormalities and short stature are characteristics that can be used to support the diagnosis. The gene responsible for the disease has been identified and genetic testing is now available. Though useful in diagnostics, a genetic test does not surmount the need for careful clinical assessment and monitoring of all patients.

MRI imaging can be used to detect whether the abducens nerve is present.

Potocki–Shaffer syndrome can be detected through array comparative genomic hybridization (aCGH).

Some symptoms can be managed with drug therapy, surgery and rehabilitation, genetic counselling, and palliative care.

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

Cytogenetic preparations that have been stained by either Giemsa or C-banding techniques will show two characteristic chromosomal abnormalities. The first chromosomal abnormality is called premature centromere separation (PCS) and is the most likely pathogenic mechanism for Roberts syndrome. Chromosomes that have PCS will have their centromeres separate during metaphase rather than anaphase (one phase earlier than normal chromosomes). The second chromosomal abnormality is called heterochromatin repulsion (HR). Chromosomes that have HR experience separation of the heterochromatic regions during metaphase. Chromosomes with these two abnormalities will display a "railroad track" appearance because of the absence of primary constriction and repulsion at the heterochromatic regions. The heterochromatic regions are the areas near the centromeres and nucleolar organizers. Carrier status cannot be determined by cytogenetic testing. Other common findings of cytogenetic testing on Roberts syndrome patients are listed below.

- Aneuploidy- the occurrence of one or more extra or missing chromosomes

- Micronucleation- nucleus is smaller than normal

- Multilobulated Nuclei- the nucleus has more than one lobe

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 is no cure and no standard course of treatment for Coffin–Lowry syndrome. Treatment is symptomatic and supportive, and may include occupational, physical and speech therapy and educational services.

The treatments of kabuki syndrome are still being developed due to its genetic nature. The first step to treatment is diagnosis. After diagnosis, the treatment of medical conditions can often be treated by medical intervention. There are also options in psychotherapy for young children with this disorder, as well as the family of the child. Genetic counseling is available as a preventative treatment for kabuki syndrome because it can be inherited and expressed by only having one copy of the mutated gene.

The diagnosis of this syndrome can be done via the test "Branchiootorenal syndrome via the SIX5 Gene" whose purpose is mutation confirmation and risk assessment (screening).

Diagnosis often can be made through clinical examination and urine tests (excess mucopolysaccharides are excreted in the urine). Enzyme assays (testing a variety of cells or body fluids in culture for enzyme deficiency) are also used to provide definitive diagnosis of one of the mucopolysaccharidoses. Prenatal diagnosis using amniocentesis and chorionic villus sampling can verify if a fetus either carries a copy of the defective gene or is affected with the disorder. Genetic counseling can help parents who have a family history of the mucopolysaccharidoses determine if they are carrying the mutated gene that causes the disorders.

Diagnosis depends on the clinical scenario. However, karyotyping is an essential test for diagnosis.

In terms of diagnosing Bannayan–Riley–Ruvalcaba syndrome there is no current method outside the physical characteristics that may be present as signs/symptoms. There are, however, multiple molecular genetics tests (and cytogenetic test) to determine Bannayan–Riley–Ruvalcaba syndrome.

Electroencephalography (EEG) in one patient showed epileptiformic activities in the frontal and frontotemporal areas as well as increased spike waves while the patient was sleeping. Another patient's EEG showed occipital rhythms in background activity that was abnormal, focal discharges over the temporal lobe, and multifocial epileptiform activity. Several patients showed a loss of normal background activity.