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Noonan syndrome 8(NS8)

MedGen UID:
815563
Concept ID:
C3809233
Disease or Syndrome
Synonym: NS8
 
Gene (location): RIT1 (1q22)
 
Monarch Initiative: MONDO:0014143
OMIM®: 615355

Disease characteristics

Excerpted from the GeneReview: Noonan Syndrome
Noonan syndrome (NS) is characterized by characteristic facies, short stature, congenital heart defect, and developmental delay of variable degree. Other findings can include broad or webbed neck, unusual chest shape with superior pectus carinatum and inferior pectus excavatum, cryptorchidism, varied coagulation defects, lymphatic dysplasias, and ocular abnormalities. Although birth length is usually normal, final adult height approaches the lower limit of normal. Congenital heart disease occurs in 50%-80% of individuals. Pulmonary valve stenosis, often with dysplasia, is the most common heart defect and is found in 20%-50% of individuals. Hypertrophic cardiomyopathy, found in 20%-30% of individuals, may be present at birth or develop in infancy or childhood. Other structural defects include atrial and ventricular septal defects, branch pulmonary artery stenosis, and tetralogy of Fallot. Up to one fourth of affected individuals have mild intellectual disability, and language impairments in general are more common in NS than in the general population. [from GeneReviews]
Authors:
Amy E Roberts   view full author information

Additional descriptions

From OMIM
Noonan syndrome-8 is an autosomal dominant disorder characterized by short stature, distinctive facial features, and a high incidence of congenital heart defects and hypertrophic cardiomyopathy. A subset of patients show intellectual disabilities (summary by Aoki et al., 2013). For a phenotypic description and a discussion of genetic heterogeneity of Noonan syndrome, see NS1 (163950).  http://www.omim.org/entry/615355
From MedlinePlus Genetics
Noonan syndrome is one of a group of related conditions, collectively known as RASopathies. These conditions all have similar signs and symptoms and are caused by changes in the same cell signaling pathway. In addition to Noonan syndrome, the RASopathies include cardiofaciocutaneous syndrome, Costello syndrome, neurofibromatosis type 1, Legius syndrome, and Noonan syndrome with multiple lentigines.

Some people with Noonan syndrome develop cancer, particularly those involving the blood-forming cells (leukemia). It has been estimated that children with Noonan syndrome have an eightfold increased risk of developing leukemia or other cancers over age-matched peers.

Noonan syndrome can cause a variety of other signs and symptoms. Most children diagnosed with Noonan syndrome have normal intelligence, but a few have special educational needs, and some have intellectual disability. Some affected individuals have vision or hearing problems. Affected infants may have feeding problems, which typically get better by age 1 or 2 years. Infants with Noonan syndrome may be born with puffy hands and feet caused by a buildup of fluid (lymphedema), which can go away on its own. Older individuals can also develop lymphedema, usually in the ankles and lower legs.

Adolescent males with Noonan syndrome typically experience delayed puberty. They go through puberty starting at age 13 or 14 and have a reduced pubertal growth spurt that results in shortened stature. Most males with Noonan syndrome have undescended testes (cryptorchidism), which may contribute to infertility (inability to father a child) later in life. Females with Noonan syndrome can experience delayed puberty but most have normal puberty and fertility.

A variety of bleeding disorders have been associated with Noonan syndrome. Some affected individuals have excessive bruising, nosebleeds, or prolonged bleeding following injury or surgery. Rarely, women with Noonan syndrome who have a bleeding disorder have excessive bleeding during menstruation (menorrhagia) or childbirth.

Most people with Noonan syndrome have some form of critical congenital heart disease. The most common heart defect in these individuals is a narrowing of the valve that controls blood flow from the heart to the lungs (pulmonary valve stenosis). Some have hypertrophic cardiomyopathy, which enlarges and weakens the heart muscle.

Individuals with Noonan syndrome often have either a sunken chest (pectus excavatum) or a protruding chest (pectus carinatum). Some affected people may also have an abnormal side-to-side curvature of the spine (scoliosis).

Between 50 and 70 percent of individuals with Noonan syndrome have short stature. At birth, they are usually a normal length and weight, but growth slows over time. Abnormal levels of growth hormone, a protein that is necessary for the normal growth of the body's bones and tissues, may contribute to the slow growth.

People with Noonan syndrome have distinctive facial features such as a deep groove in the area between the nose and mouth (philtrum), widely spaced eyes that are usually pale blue or blue-green in color, and low-set ears that are rotated backward. Affected individuals may have a high arch in the roof of the mouth (high-arched palate), poor teeth alignment, and a small lower jaw (micrognathia). Many children with Noonan syndrome have a short neck, and both children and adults may have excess neck skin (also called webbing) and a low hairline at the back of the neck.

Noonan syndrome is a condition that affects many areas of the body. It is characterized by mildly unusual facial features, short stature, heart defects, bleeding problems, skeletal malformations, and many other signs and symptoms.  https://medlineplus.gov/genetics/condition/noonan-syndrome

Clinical features

From HPO
Cryptorchidism
MedGen UID:
8192
Concept ID:
C0010417
Congenital Abnormality
Cryptorchidism, or failure of testicular descent, is a common human congenital abnormality with a multifactorial etiology that likely reflects the involvement of endocrine, environmental, and hereditary factors. Cryptorchidism can result in infertility and increases risk for testicular tumors. Testicular descent from abdomen to scrotum occurs in 2 distinct phases: the transabdominal phase and the inguinoscrotal phase (summary by Gorlov et al., 2002).
Hypertrophic cardiomyopathy
MedGen UID:
2881
Concept ID:
C0007194
Disease or Syndrome
Hypertrophic cardiomyopathy (HCM) is defined by the presence of increased ventricular wall thickness or mass in the absence of loading conditions (hypertension, valve disease) sufficient to cause the observed abnormality.
Patent ductus arteriosus
MedGen UID:
4415
Concept ID:
C0013274
Congenital Abnormality
In utero, the ductus arteriosus (DA) serves to divert ventricular output away from the lungs and toward the placenta by connecting the main pulmonary artery to the descending aorta. A patent ductus arteriosus (PDA) in the first 3 days of life is a physiologic shunt in healthy term and preterm newborn infants, and normally is substantially closed within about 24 hours after bith and completely closed after about three weeks. Failure of physiologcal closure is referred to a persistent or patent ductus arteriosus (PDA). Depending on the degree of left-to-right shunting, PDA can have clinical consequences.
Atrial septal defect
MedGen UID:
6753
Concept ID:
C0018817
Congenital Abnormality
Atrial septal defect (ASD) is a congenital abnormality of the interatrial septum that enables blood flow between the left and right atria via the interatrial septum.
Ventricular septal defect
MedGen UID:
42366
Concept ID:
C0018818
Congenital Abnormality
A hole between the two bottom chambers (ventricles) of the heart. The defect is centered around the most superior aspect of the ventricular septum.
Mitral regurgitation
MedGen UID:
7670
Concept ID:
C0026266
Disease or Syndrome
An abnormality of the mitral valve characterized by insufficiency or incompetence of the mitral valve resulting in retrograde leaking of blood through the mitral valve upon ventricular contraction.
Left ventricular hypertrophy
MedGen UID:
57442
Concept ID:
C0149721
Disease or Syndrome
Enlargement or increased size of the heart left ventricle.
Pulmonic stenosis
MedGen UID:
408291
Concept ID:
C1956257
Disease or Syndrome
A narrowing of the right ventricular outflow tract that can occur at the pulmonary valve (valvular stenosis), below the pulmonary valve (infundibular stenosis), or above the pulmonary valve (supravalvar stenosis).
Short stature
MedGen UID:
87607
Concept ID:
C0349588
Finding
A height below that which is expected according to age and gender norms. Although there is no universally accepted definition of short stature, many refer to "short stature" as height more than 2 standard deviations below the mean for age and gender (or below the 3rd percentile for age and gender dependent norms).
Large for gestational age
MedGen UID:
341215
Concept ID:
C1848395
Finding
The term large for gestational age applies to babies whose birth weight lies above the 90th percentile for that gestational age.
Failure to thrive
MedGen UID:
746019
Concept ID:
C2315100
Disease or Syndrome
Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm.
Feeding difficulties
MedGen UID:
65429
Concept ID:
C0232466
Finding
Impaired ability to eat related to problems gathering food and getting ready to suck, chew, or swallow it.
Low-set ears
MedGen UID:
65980
Concept ID:
C0239234
Congenital Abnormality
Upper insertion of the ear to the scalp below an imaginary horizontal line drawn between the inner canthi of the eye and extending posteriorly to the ear.
Intellectual disability
MedGen UID:
811461
Concept ID:
C3714756
Mental or Behavioral Dysfunction
Intellectual disability, previously referred to as mental retardation, is characterized by subnormal intellectual functioning that occurs during the developmental period. It is defined by an IQ score below 70.
Relative macrocephaly
MedGen UID:
338607
Concept ID:
C1849075
Congenital Abnormality
A relatively mild degree of macrocephaly in which the head circumference is not above two standard deviations from the mean, but appears dysproportionately large when other factors such as body stature are taken into account.
Abnormal sternum morphology
MedGen UID:
349830
Concept ID:
C1860493
Anatomical Abnormality
An anomaly of the sternum, also known as the breastbone.
Pleural effusion
MedGen UID:
10805
Concept ID:
C0032227
Disease or Syndrome
The presence of an excessive amount of fluid in the pleural cavity.
Webbed neck
MedGen UID:
113154
Concept ID:
C0221217
Congenital Abnormality
Pterygium colli is a congenital skin fold that runs along the sides of the neck down to the shoulders. It involves an ectopic fibrotic facial band superficial to the trapezius muscle. Excess hair-bearing skin is also present and extends down the cervical region well beyond the normal hairline.
Downslanted palpebral fissures
MedGen UID:
98391
Concept ID:
C0423110
Finding
The palpebral fissure inclination is more than two standard deviations below the mean.
Short neck
MedGen UID:
99267
Concept ID:
C0521525
Finding
Diminished length of the neck.
Epicanthus
MedGen UID:
151862
Concept ID:
C0678230
Congenital Abnormality
Epicanthus is a condition in which a fold of skin stretches from the upper to the lower eyelid, partially covering the inner canthus. Usher (1935) noted that epicanthus is a normal finding in the fetus of all races. Epicanthus also occurs in association with hereditary ptosis (110100).
Hyperpigmentation of the skin
MedGen UID:
57992
Concept ID:
C0162834
Pathologic Function
A darkening of the skin related to an increase in melanin production and deposition.
Hyperextensible skin
MedGen UID:
66023
Concept ID:
C0241074
Finding
A condition in which the skin can be stretched beyond normal, and then returns to its initial position.
Curly hair
MedGen UID:
488919
Concept ID:
C0558165
Finding
Hyperkeratosis
MedGen UID:
209030
Concept ID:
C0870082
Disease or Syndrome
Hyperkeratosis is thickening of the outer layer of the skin, the stratum corneum, which is composed of large, polyhedral, plate-like envelopes filled with keratin which are the dead cells that have migrated up from the stratum granulosum.
Palmoplantar cutis laxa
MedGen UID:
341602
Concept ID:
C1856714
Finding
Loose, wrinkled skin of hands and feet.
Polyhydramnios
MedGen UID:
6936
Concept ID:
C0020224
Pathologic Function
The presence of excess amniotic fluid in the uterus during pregnancy.
Ptosis
MedGen UID:
2287
Concept ID:
C0005745
Disease or Syndrome
The upper eyelid margin is positioned 3 mm or more lower than usual and covers the superior portion of the iris (objective); or, the upper lid margin obscures at least part of the pupil (subjective).
Hypertelorism
MedGen UID:
9373
Concept ID:
C0020534
Finding
Although hypertelorism means an excessive distance between any paired organs (e.g., the nipples), the use of the word has come to be confined to ocular hypertelorism. Hypertelorism occurs as an isolated feature and is also a feature of many syndromes, e.g., Opitz G syndrome (see 300000), Greig cephalopolysyndactyly (175700), and Noonan syndrome (163950) (summary by Cohen et al., 1995).

Professional guidelines

PubMed

Wu X, Wu J, Yuan Y, Yang L, Yu L
Mol Genet Genomic Med 2023 Nov;11(11):e2266. Epub 2023 Aug 1 doi: 10.1002/mgg3.2266. PMID: 37525886Free PMC Article
Briggs B, Savla D, Ramchandar N, Dimmock D, Le D, Thornburg CD
J Pediatr 2020 May;220:154-158.e6. Epub 2020 Feb 25 doi: 10.1016/j.jpeds.2020.01.048. PMID: 32111381
Romano AA
Pediatr Endocrinol Rev 2019 May;16(Suppl 2):459-464. doi: 10.17458/per.vol16.2019.r.growthhormonenoonan. PMID: 31115197

Recent clinical studies

Etiology

Chow CA, Campbell KH, Chou JC, Elder RW
Cardiol Young 2022 Dec;32(12):1925-1929. Epub 2022 Jan 17 doi: 10.1017/S104795112100514X. PMID: 35034678
André T, Shiu KK, Kim TW, Jensen BV, Jensen LH, Punt C, Smith D, Garcia-Carbonero R, Benavides M, Gibbs P, de la Fouchardiere C, Rivera F, Elez E, Bendell J, Le DT, Yoshino T, Van Cutsem E, Yang P, Farooqui MZH, Marinello P, Diaz LA Jr; KEYNOTE-177 Investigators
N Engl J Med 2020 Dec 3;383(23):2207-2218. doi: 10.1056/NEJMoa2017699. PMID: 33264544
Athota JP, Bhat M, Nampoothiri S, Gowrishankar K, Narayanachar SG, Puttamallesh V, Farooque MO, Shetty S
BMC Med Genet 2020 Mar 12;21(1):50. doi: 10.1186/s12881-020-0986-5. PMID: 32164556Free PMC Article
Ridker PM, Everett BM, Pradhan A, MacFadyen JG, Solomon DH, Zaharris E, Mam V, Hasan A, Rosenberg Y, Iturriaga E, Gupta M, Tsigoulis M, Verma S, Clearfield M, Libby P, Goldhaber SZ, Seagle R, Ofori C, Saklayen M, Butman S, Singh N, Le May M, Bertrand O, Johnston J, Paynter NP, Glynn RJ; CIRT Investigators
N Engl J Med 2019 Feb 21;380(8):752-762. Epub 2018 Nov 10 doi: 10.1056/NEJMoa1809798. PMID: 30415610Free PMC Article
Yamamoto GL, Aguena M, Gos M, Hung C, Pilch J, Fahiminiya S, Abramowicz A, Cristian I, Buscarilli M, Naslavsky MS, Malaquias AC, Zatz M, Bodamer O, Majewski J, Jorge AA, Pereira AC, Kim CA, Passos-Bueno MR, Bertola DR
J Med Genet 2015 Jun;52(6):413-21. Epub 2015 Mar 20 doi: 10.1136/jmedgenet-2015-103018. PMID: 25795793

Diagnosis

Danowitz M, Grimberg A
Adv Pediatr 2022 Aug;69(1):203-217. Epub 2022 Jun 17 doi: 10.1016/j.yapd.2022.03.005. PMID: 35985710Free PMC Article
Farncombe KM, Thain E, Barnett-Tapia C, Sadeghian H, Kim RH
BMC Med Genomics 2022 Jul 15;15(1):160. doi: 10.1186/s12920-022-01304-x. PMID: 35840934Free PMC Article
Chow CA, Campbell KH, Chou JC, Elder RW
Cardiol Young 2022 Dec;32(12):1925-1929. Epub 2022 Jan 17 doi: 10.1017/S104795112100514X. PMID: 35034678
Athota JP, Bhat M, Nampoothiri S, Gowrishankar K, Narayanachar SG, Puttamallesh V, Farooque MO, Shetty S
BMC Med Genet 2020 Mar 12;21(1):50. doi: 10.1186/s12881-020-0986-5. PMID: 32164556Free PMC Article
Yamamoto GL, Aguena M, Gos M, Hung C, Pilch J, Fahiminiya S, Abramowicz A, Cristian I, Buscarilli M, Naslavsky MS, Malaquias AC, Zatz M, Bodamer O, Majewski J, Jorge AA, Pereira AC, Kim CA, Passos-Bueno MR, Bertola DR
J Med Genet 2015 Jun;52(6):413-21. Epub 2015 Mar 20 doi: 10.1136/jmedgenet-2015-103018. PMID: 25795793

Therapy

Wu X, Wu J, Yuan Y, Yang L, Yu L
Mol Genet Genomic Med 2023 Nov;11(11):e2266. Epub 2023 Aug 1 doi: 10.1002/mgg3.2266. PMID: 37525886Free PMC Article
Webster ALH, Sanders MA, Patel K, Dietrich R, Noonan RJ, Lach FP, White RR, Goldfarb A, Hadi K, Edwards MM, Donovan FX, Hoogenboezem RM, Jung M, Sridhar S, Wiley TF, Fedrigo O, Tian H, Rosiene J, Heineman T, Kennedy JA, Bean L, Rosti RO, Tryon R, Gonzalez AM, Rosenberg A, Luo JD, Carroll TS, Shroff S, Beaumont M, Velleuer E, Rastatter JC, Wells SI, Surrallés J, Bagby G, MacMillan ML, Wagner JE, Cancio M, Boulad F, Scognamiglio T, Vaughan R, Beaumont KG, Koren A, Imielinski M, Chandrasekharappa SC, Auerbach AD, Singh B, Kutler DI, Campbell PJ, Smogorzewska A
Nature 2022 Dec;612(7940):495-502. Epub 2022 Nov 30 doi: 10.1038/s41586-022-05253-4. PMID: 36450981Free PMC Article
Danowitz M, Grimberg A
Adv Pediatr 2022 Aug;69(1):203-217. Epub 2022 Jun 17 doi: 10.1016/j.yapd.2022.03.005. PMID: 35985710Free PMC Article
André T, Shiu KK, Kim TW, Jensen BV, Jensen LH, Punt C, Smith D, Garcia-Carbonero R, Benavides M, Gibbs P, de la Fouchardiere C, Rivera F, Elez E, Bendell J, Le DT, Yoshino T, Van Cutsem E, Yang P, Farooqui MZH, Marinello P, Diaz LA Jr; KEYNOTE-177 Investigators
N Engl J Med 2020 Dec 3;383(23):2207-2218. doi: 10.1056/NEJMoa2017699. PMID: 33264544
Ridker PM, Everett BM, Pradhan A, MacFadyen JG, Solomon DH, Zaharris E, Mam V, Hasan A, Rosenberg Y, Iturriaga E, Gupta M, Tsigoulis M, Verma S, Clearfield M, Libby P, Goldhaber SZ, Seagle R, Ofori C, Saklayen M, Butman S, Singh N, Le May M, Bertrand O, Johnston J, Paynter NP, Glynn RJ; CIRT Investigators
N Engl J Med 2019 Feb 21;380(8):752-762. Epub 2018 Nov 10 doi: 10.1056/NEJMoa1809798. PMID: 30415610Free PMC Article

Prognosis

Tsuda E, Ito Y, Kato Y, Sakaguchi H, Ohuchi H, Kurosaki K
J Cardiol 2022 Dec;80(6):557-562. Epub 2022 Aug 10 doi: 10.1016/j.jjcc.2022.07.016. PMID: 35961804
Papadopoulos G, Papadopoulou A, Kosma K, Papadimitriou A, Papaevangelou V, Kanaka-Gantenbein C, Bountouvi E, Kitsiou-Tzeli S
Eur J Pediatr 2022 Oct;181(10):3691-3700. Epub 2022 Jul 29 doi: 10.1007/s00431-022-04574-w. PMID: 35904599
Davico C, D'Alessandro R, Borgogno M, Campagna F, Torta F, Ricci F, Amianto F, Vittorini R, Carli D, Mussa A, Vitiello B, Ferrero GB
Eur J Pediatr 2022 Aug;181(8):2919-2926. Epub 2022 May 16 doi: 10.1007/s00431-022-04497-6. PMID: 35575813
Ahmed A, Naidu A
J Clin Pathol 2021 Aug;74(8):483-490. Epub 2021 Apr 15 doi: 10.1136/jclinpath-2020-206858. PMID: 33858937
Ridker PM, Everett BM, Pradhan A, MacFadyen JG, Solomon DH, Zaharris E, Mam V, Hasan A, Rosenberg Y, Iturriaga E, Gupta M, Tsigoulis M, Verma S, Clearfield M, Libby P, Goldhaber SZ, Seagle R, Ofori C, Saklayen M, Butman S, Singh N, Le May M, Bertrand O, Johnston J, Paynter NP, Glynn RJ; CIRT Investigators
N Engl J Med 2019 Feb 21;380(8):752-762. Epub 2018 Nov 10 doi: 10.1056/NEJMoa1809798. PMID: 30415610Free PMC Article

Clinical prediction guides

PHOSP-COVID Collaborative Group
Lancet Respir Med 2022 Aug;10(8):761-775. Epub 2022 Apr 23 doi: 10.1016/S2213-2600(22)00127-8. PMID: 35472304Free PMC Article
Ahmed A, Naidu A
J Clin Pathol 2021 Aug;74(8):483-490. Epub 2021 Apr 15 doi: 10.1136/jclinpath-2020-206858. PMID: 33858937
André T, Shiu KK, Kim TW, Jensen BV, Jensen LH, Punt C, Smith D, Garcia-Carbonero R, Benavides M, Gibbs P, de la Fouchardiere C, Rivera F, Elez E, Bendell J, Le DT, Yoshino T, Van Cutsem E, Yang P, Farooqui MZH, Marinello P, Diaz LA Jr; KEYNOTE-177 Investigators
N Engl J Med 2020 Dec 3;383(23):2207-2218. doi: 10.1056/NEJMoa2017699. PMID: 33264544
Athota JP, Bhat M, Nampoothiri S, Gowrishankar K, Narayanachar SG, Puttamallesh V, Farooque MO, Shetty S
BMC Med Genet 2020 Mar 12;21(1):50. doi: 10.1186/s12881-020-0986-5. PMID: 32164556Free PMC Article
Cobben JM, Oostra RJ, van Dijk FS
Eur J Med Genet 2014 Aug;57(8):414-7. Epub 2014 May 10 doi: 10.1016/j.ejmg.2014.04.017. PMID: 24821303

Recent systematic reviews

Cox TP, Vance CJ, Daley SK, Papendieck C, McGregor H, Kuo P, Witte MH
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