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Noonan syndrome 9(NS9)

MedGen UID:
896352
Concept ID:
C4225282
Disease or Syndrome
Synonym: NS9
 
Gene (location): SOS2 (14q21.3)
 
Monarch Initiative: MONDO:0014691
OMIM®: 616559

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 is an autosomal dominant disorder characterized by short stature, craniofacial dysmorphism, short and/or webbed neck, cardiac abnormalities, cryptorchidism, and coagulation defects (summary by Yamamoto et al., 2015). For a phenotypic description and a discussion of genetic heterogeneity of Noonan syndrome, see NS1 (163950).  http://www.omim.org/entry/616559
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).
Hydroureter
MedGen UID:
101073
Concept ID:
C0521620
Anatomical Abnormality
The distention of the ureter with urine.
Coarctation of aorta
MedGen UID:
1617
Concept ID:
C0003492
Congenital Abnormality
Coarctation of the aorta is a narrowing or constriction of a segment of the aorta.
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.
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).
Global developmental delay
MedGen UID:
107838
Concept ID:
C0557874
Finding
A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.
Prolonged prothrombin time
MedGen UID:
208879
Concept ID:
C0853225
Finding
Increased time to coagulation in the prothrombin time test, which is a measure of the extrinsic pathway of coagulation. The results of the prothrombin time test are often expressed in terms of the International normalized ratio (INR), which is calculated as a ratio of the patient's prothrombin time (PT) to a control PT standardized for the potency of the thromboplastin reagent developed by the World Health Organization (WHO) using the formula
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.
Sparse eyebrow
MedGen UID:
371332
Concept ID:
C1832446
Finding
Decreased density/number of eyebrow hairs.
Keratosis pilaris
MedGen UID:
82664
Concept ID:
C0263383
Disease or Syndrome
An anomaly of the hair follicles of the skin that typically presents as small, rough, brown folliculocentric papules distributed over characteristic areas of the skin, particularly the outer-upper arms and thighs.
Curly hair
MedGen UID:
488919
Concept ID:
C0558165
Finding
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).
Prominent corneal nerve fibers
MedGen UID:
866878
Concept ID:
C4021233
Anatomical Abnormality
Abnormal prominence of the corneal nerve fibers.

Term Hierarchy

Professional guidelines

PubMed

Tamburrino F, Mazzanti L, Scarano E, Gibertoni D, Sirolli M, Zioutas M, Schiavariello C, Perri A, Mantovani A, Rossi C, Tartaglia M, Pession A
Front Endocrinol (Lausanne) 2023;14:1209339. Epub 2023 Jul 31 doi: 10.3389/fendo.2023.1209339. PMID: 37588986Free PMC Article
Noonan EM, Farrell TW
Am Fam Physician 2016 May 1;93(9):764-70. PMID: 27175954
Tartaglia M, Kalidas K, Shaw A, Song X, Musat DL, van der Burgt I, Brunner HG, Bertola DR, Crosby A, Ion A, Kucherlapati RS, Jeffery S, Patton MA, Gelb BD
Am J Hum Genet 2002 Jun;70(6):1555-63. Epub 2002 May 1 doi: 10.1086/340847. PMID: 11992261Free PMC Article

Recent clinical studies

Etiology

Tamburrino F, Mazzanti L, Scarano E, Gibertoni D, Sirolli M, Zioutas M, Schiavariello C, Perri A, Mantovani A, Rossi C, Tartaglia M, Pession A
Front Endocrinol (Lausanne) 2023;14:1209339. Epub 2023 Jul 31 doi: 10.3389/fendo.2023.1209339. PMID: 37588986Free PMC Article
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
Mohan P, Lemoine J, Trotter C, Rakova I, Billings P, Peacock S, Kao CY, Wang Y, Xia F, Eng CM, Benn P
Ultrasound Obstet Gynecol 2022 Jan;59(1):33-39. doi: 10.1002/uog.23756. PMID: 34358384Free 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
Tartaglia M, Kalidas K, Shaw A, Song X, Musat DL, van der Burgt I, Brunner HG, Bertola DR, Crosby A, Ion A, Kucherlapati RS, Jeffery S, Patton MA, Gelb BD
Am J Hum Genet 2002 Jun;70(6):1555-63. Epub 2002 May 1 doi: 10.1086/340847. PMID: 11992261Free PMC Article

Diagnosis

Tamburrino F, Mazzanti L, Scarano E, Gibertoni D, Sirolli M, Zioutas M, Schiavariello C, Perri A, Mantovani A, Rossi C, Tartaglia M, Pession A
Front Endocrinol (Lausanne) 2023;14:1209339. Epub 2023 Jul 31 doi: 10.3389/fendo.2023.1209339. PMID: 37588986Free PMC Article
Yang Y, Woo JH, Ali A
Cornea 2022 Nov 1;41(11):1462-1464. Epub 2022 Jul 6 doi: 10.1097/ICO.0000000000003078. PMID: 35867656
Mohan P, Lemoine J, Trotter C, Rakova I, Billings P, Peacock S, Kao CY, Wang Y, Xia F, Eng CM, Benn P
Ultrasound Obstet Gynecol 2022 Jan;59(1):33-39. doi: 10.1002/uog.23756. PMID: 34358384Free PMC Article
Leach NT, Wilson Mathews DR, Rosenblum LS, Zhou Z, Zhu H, Heim RA
Genet Med 2019 Feb;21(2):417-425. Epub 2018 Jun 15 doi: 10.1038/s41436-018-0062-0. PMID: 29907801
Mattina T, Perrotta CS, Grossfeld P
Orphanet J Rare Dis 2009 Mar 7;4:9. doi: 10.1186/1750-1172-4-9. PMID: 19267933Free PMC Article

Therapy

Pittet LF, Messina NL, Orsini F, Moore CL, Abruzzo V, Barry S, Bonnici R, Bonten M, Campbell J, Croda J, Dalcolmo M, Gardiner K, Gell G, Germano S, Gomes-Silva A, Goodall C, Gwee A, Jamieson T, Jardim B, Kollmann TR, Lacerda MVG, Lee KJ, Lucas M, Lynn DJ, Manning L, Marshall HS, McDonald E, Munns CF, Nicholson S, O'Connell A, de Oliveira RD, Perlen S, Perrett KP, Prat-Aymerich C, Richmond PC, Rodriguez-Baño J, Dos Santos G, da Silva PV, Teo JW, Villanueva P, Warris A, Wood NJ, Davidson A, Curtis N; BRACE Trial Consortium Group
N Engl J Med 2023 Apr 27;388(17):1582-1596. doi: 10.1056/NEJMoa2212616. PMID: 37099341Free 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
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
Romano AA
Pediatr Endocrinol Rev 2019 May;16(Suppl 2):459-464. doi: 10.17458/per.vol16.2019.r.growthhormonenoonan. PMID: 31115197
Noonan EM, Farrell TW
Am Fam Physician 2016 May 1;93(9):764-70. PMID: 27175954

Prognosis

Boleti O, Norrish G, Field E, Dady K, Summers K, Nepali G, Bhole V, Uzun O, Wong A, Daubeney PEF, Stuart G, Fernandes P, McLeod K, Ilina M, Ali MNL, Bharucha T, Donne GD, Brown E, Linter K, Jones CB, Searle J, Regan W, Mathur S, Boyd N, Reinhardt Z, Duignan S, Prendiville T, Adwani S, Kaski JP
ESC Heart Fail 2024 Apr;11(2):923-936. Epub 2024 Jan 13 doi: 10.1002/ehf2.14637. PMID: 38217456Free PMC Article
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
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
Calcagni G, Unolt M, Digilio MC, Baban A, Versacci P, Tartaglia M, Baldini A, Marino B
Expert Rev Mol Diagn 2017 Sep;17(9):861-870. Epub 2017 Aug 3 doi: 10.1080/14737159.2017.1360766. PMID: 28745539
Tosti A, Peluso AM, Misciali C, Venturo N, Patrizi A, Fanti PA
Arch Dermatol 1997 Sep;133(9):1089-93. PMID: 9301585

Clinical prediction guides

Edouard T, Cartault A
Ann Endocrinol (Paris) 2022 Jun;83(3):203-206. Epub 2022 Apr 27 doi: 10.1016/j.ando.2022.04.008. PMID: 35489412
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
Mohan P, Lemoine J, Trotter C, Rakova I, Billings P, Peacock S, Kao CY, Wang Y, Xia F, Eng CM, Benn P
Ultrasound Obstet Gynecol 2022 Jan;59(1):33-39. doi: 10.1002/uog.23756. PMID: 34358384Free 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
Leach NT, Wilson Mathews DR, Rosenblum LS, Zhou Z, Zhu H, Heim RA
Genet Med 2019 Feb;21(2):417-425. Epub 2018 Jun 15 doi: 10.1038/s41436-018-0062-0. PMID: 29907801

Recent systematic reviews

Olwi D, Day F, Ong K
Horm Res Paediatr 2024;97(1):1-10. Epub 2023 Apr 19 doi: 10.1159/000530578. PMID: 37075730

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