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.

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.

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.

Since the symptoms caused by this disease are present at birth, there is no “cure.” The best cure that scientists are researching is awareness and genetic testing to determine risk factors and increase knowledgeable family planning. Prevention is the only option at this point in time for a cure.

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.

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.

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.

Because the variability of this disease is so great and the way that it reveals itself could be multi-faceted; once diagnosed, a multidisciplinary team is recommended to treat the disease and should include a craniofacial surgeon, ophthalmologist, pediatrician, pediatric urologist, cardiologist, pulmonologist, speech pathologist, and a medical geneticist. Several important steps must be followed, as well.

- Past medical history

- Physical examination with special attention to size and measurements of facial features, palate, heart, genitourinary system and lower respiratory system

- Eye evaluation

- Hypospadias assessment by urologist

- Laryngoscopy and chest x-ray for difficulties with breathing/swallowing

- Cleft lip/palate assessment by craniofacial surgeon

- Assessment of standard age developmental and intellectual abilities

- Anal position assessment

- Echocardiogram

- Cranial imaging

Many surgical repairs may be needed, as assessed by professionals. Furthermore, special education therapies and psychoemotional therapies may be required, as well. In some cases, antireflux drugs can be prescribed until risk of breathing and swallowing disorders are removed. Genetic counseling is highly advised to help explain who else in the family may be at risk for the disease and to help guide family planning decisions in the future.

Because of its wide variability in which defects will occur, there is no known mortality rate specifically for the disease. However, the leading cause of death for people with Opitz G/BBB syndrome is due to infant death caused by aspiration due to esophageal, pharyngeal or laryngeal defects.

Fortunately, to date there are no factors that can increase the expression of symptoms of this disease. All abnormalities and symptoms are present at birth.

Syndactyly and other deformities are typically observed and diagnosed at birth. Long QT syndrome sometimes presents itself as a complication due to surgery to correct syndactyly. Other times, children collapse spontaneously while playing. In all cases it is confirmed with ECG measurements. Sequencing of the CACNA1C gene further confirms the diagnosis.

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 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.

According to the Williams Syndrome Association, diagnosis of Williams syndrome begins with recognition of physical symptoms and markers, which is followed by a confirmatory genetic test. The physical signs that often indicate a suspected case of Williams syndrome include puffiness around the eyes, a long philtrum, and a pattern in the iris. Physiological symptoms that often contribute to a Williams syndrome diagnosis are cardiovascular problems, particularly aortic or pulmonary stenosis, as well as feeding disturbance in infants. Developmental delays are often taken as an initial sign of the syndrome, as well.

If a physician suspects a case of Williams syndrome, the diagnosis is confirmed using one of two possible genetic tests: micro-array analysis or the fluorescent in situ hybridization (FISH) test. The FISH test examines chromosome #7 and probes for the existence of two copies of the elastin gene. Since 98-99% of individuals with Williams syndrome lack half of the 7q11.23 region of chromosome #7, where the elastin gene is located, the presence of only one copy of the gene is a strong sign of the syndrome. This confirmatory genetic test has been validated in epidemiological studies of the syndrome, and has been demonstrated to be a more effective method of identifying Williams syndrome than previous methods, which often relied on the presence of cardiovascular problems and facial features (which, while common, are not always present).

Some diagnostic studies suggest that reliance on facial features to identify Williams syndrome may cause a misdiagnosis of the condition. Among the more reliable features suggestive of Williams are congenital heart disease, periorbital fullness ("puffy" eyes), and the presence of a long smooth philtrum. Less reliable signs of the syndrome include anteverted nostrils, a wide mouth, and an elongated neck. Researchers indicate that even with significant clinical experience, it is difficult to reliably identify Williams syndrome based on facial features alone.

Diagnosis is made based on features as well as by the very early onset of serious eye and ear disease. Because Marshall syndrome is an autosomal dominant hereditary disease, physicians can also note the characteristic appearance of the biological parent of the child. There are no tests for Stickler syndrome or Marshall syndrome. Some families with Stickler syndrome have been shown to have mutations in the Type II collagen gene on chromosome 1. However, other families do not show the linkage to the collagen gene. It is an area of active research, also the genetic testing being expensive supports that the diagnosis is made depending on the features.

The diagnosis of Perlman syndrome is based on observed phenotypic features and confirmed by histological examination of the kidneys. Prenatal diagnosis is possible for families that have a genetic disposition for Perlman syndrome although there is no conclusive laboratory test to confirm the diagnosis. Fetal overgrowth, particularly with an occipitofrontal circumference (OFC) greater than the 90th centile for gestational age, as well as an excess of amniotic fluid in the amniotic sac (polyhydramnios), may be the first signs of Perlman. Using ultrasound diagnosis, Perlman syndrome has been detected at 18 weeks. During the first trimester, the common abnormalities of the syndrome observed by ultrasound include cystic hygroma and a thickened nuchal lucency. Common findings for the second and third trimesters include macrosomia, enlarged kidneys, renal tumors (both hamartoma and Wilms), cardiac abnormalities and visceromegaly.

Prompt recognition and identification of the disorder along with accurate follow-up and clinical assistance is recommended as the prognosis for Perlman is severe and associated with a high neonatal death rate.

Prognoses for 3C syndrome vary widely based on the specific constellation of symptoms seen in an individual. Typically, the gravity of the prognosis correlates with the severity of the cardiac abnormalities. For children with less severe cardiac abnormalities, the developmental prognosis depends on the cerebellar abnormalities that are present. Severe cerebellar hypoplasia is associated with growth and speech delays, as well as hypotonia and general growth deficiencies.

More than 80% of children with Patau syndrome die within the first year of life. Children with the mosaic variation are usually affected to a lesser extent. In a retrospective Canadian study of 174 children with trisomy 13, median survival time was 12.5 days. One and ten year survival was 19.8% and 12.9% respectively.

Although LFS is usually suspected when intellectual disability and marfanoid habitus are observed together in a patient, the diagnosis of LFS can be confirmed by the presence of the p.N1007S missense mutation in the "MED12" gene.

In the differential diagnosis of LFS, another disorder that exhibits some features and symptoms of LFS and is also associated with a missense mutation of "MED12" is Opitz-Kaveggia syndrome (FGS). Common features shared by both LFS and FGS include X-linked intellectual disability, hyperactivity, macrocephaly, corpus callosum agenesis and hypotonia. Notable features of FGS that have not been reported with LFS include excessive talkativness, consistent strength in socialization skills, imperforate anus (occlusion of the anus) and ocular hypertelorism (extremely wide-set eyes).

Whereas LFS is associated with missense mutation p.N1007S, FGS is associated with missense mutation p.R961W. As both disorders originate from an identical type of mutation in the same gene, while exhibiting similar, yet distinct characteristics; LFS and FGS are considered to be allelic. In the context of "MED12", this suggests that the phenotype of each disorder is related to the way in which their respective mutations alter the "MED12" sequence and its function.

Many professionals that are likely to be involved in the treatment of those with Stickler's syndrome, include anesthesiologists, oral and maxillofacial surgeons; craniofacial surgeons; ear, nose, and throat specialists, ophthalmologists, optometrists, audiologists, speech pathologists, physical therapists and rheumatologists.

Turner syndrome may be diagnosed by amniocentesis or chorionic villus sampling during pregnancy.

Usually, fetuses with Turner syndrome can be identified by abnormal ultrasound findings ("i.e.", heart defect, kidney abnormality, cystic hygroma, ascites). In a study of 19 European registries, 67.2% of prenatally diagnosed cases of Turner Syndrome were detected by abnormalities on ultrasound. 69.1% of cases had one anomaly present, and 30.9% had two or more anomalies.

An increased risk of Turner syndrome may also be indicated by abnormal triple or quadruple maternal serum screen. The fetuses diagnosed through positive maternal serum screening are more often found to

have a mosaic karyotype than those diagnosed based on ultrasonographic abnormalities, and

conversely, those with mosaic karyotypes are less likely to have associated ultrasound abnormalities.

The prognosis for patients diagnosed with Timothy syndrome is very poor. Of 17 children analyzed in one study, 10 died at an average age of 2.5 years. Of those that did survive, 3 were diagnosed with autism, one with an autism spectrum disorder, and the last had severe delays in language development. One patient with atypical Timothy syndrome was largely normal with the exception of heart arrhythmia. Likewise, the mother of two Timothy syndrome patients also carried the mutation but lacked any obvious phenotype. In both of these cases, however, the lack of severity of the disorder was due to mosaicism.

The outcome of this disease is dependent on the severity of the cardiac defects. Approximately 1 in 3 children with this diagnosis require shunting for the hydrocephaly that is often a consequence. Some children require extra assistance or therapy for delayed psychomotor and speech development, including hypotonia.

Turner syndrome can be diagnosed postnatally at any age. Often, it is diagnosed at birth due to heart problems, an unusually wide neck or swelling of the hands and feet. However, it is also common for it to go undiagnosed for several years, typically until the girl reaches the age of puberty/adolescence and she fails to develop properly (the changes associated with puberty do not occur). In childhood, a short stature can be indicative of Turner syndrome.

A test called a karyotype, also known as a chromosome analysis, analyzes the chromosomal composition of the individual. This is the test of choice to diagnose Turner syndrome.

At the 2005 American Society of Human Genetics meeting, Francis Collins gave a presentation about a treatment he devised for children affected by Progeria. He discussed how farnesyltransferase inhibitor (FTI) affects H-Ras. After his presentation, members of the Costello Syndrome Family Network discussed the possibility of FTIs helping children with Costello syndrome. Mark Kieran, who presented at the 1st International Costello Syndrome Research Symposium in 2007, agreed that FTIs might help children with Costello syndrome. He discussed with Costello advocates what he had learned in establishing and running the Progeria clinical trial with an FTI, to help them consider next steps.

Another medication that affects H-Ras is Lovastatin, which is planned as a treatment for neurofibromatosis type I. When this was reported in mainstream news, the Costello Syndrome Professional Advisory Board was asked about its use in Costello Syndrome. Research into the effects of Lovastatin was linked with Alcino Silva, who presented his findings at the 2007 symposium. Silva also believed that the medication he was studying could help children with Costello syndrome with cognition.

A third medication that might help children with Costello syndrome is a MEK inhibitor that helps inhibit the pathway closer to the cell nucleus.