U.S. flag

An official website of the United States government

Format

Send to:

Choose Destination

Noonan syndrome 12(NS12)

MedGen UID:
1684730
Concept ID:
C5231432
Disease or Syndrome
Synonyms: NOONAN SYNDROME 12; NS12
 
Gene (location): RRAS2 (11p15.2)
 
Monarch Initiative: MONDO:0032839
OMIM®: 618624

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 description

From OMIM
Noonan syndrome-12 (NS12) is characterized by macrocephaly and a recognizable facies, including hypertelorism, downslanting palpebral fissures, and low-set ears, as well as other features consistent with a Noonan syndrome diagnosis. Inter- and intrafamilial variability has been observed (Capri et al., 2019; Niihori et al., 2019). For a general phenotypic description and a discussion of genetic heterogeneity of Noonan syndrome, see NS1 (163950).  http://www.omim.org/entry/618624

Clinical features

From HPO
Glabellar hemangioma
MedGen UID:
340224
Concept ID:
C1854408
Neoplastic Process
Proximal placement of thumb
MedGen UID:
356033
Concept ID:
C1865572
Finding
Proximal mislocalization of the thumb.
Supravalvar aortic stenosis
MedGen UID:
2001
Concept ID:
C0003499
Disease or Syndrome
Supravalvular aortic stenosis (SVAS) is a heart defect that develops before birth. This defect is a narrowing (stenosis) of the large blood vessel that carries blood from the heart to the rest of the body (the aorta). The condition is described as supravalvular because the section of the aorta that is narrowed is located just above the valve that connects the aorta with the heart (the aortic valve). Some people with SVAS also have defects in other blood vessels, most commonly stenosis of the artery from the heart to the lungs (the pulmonary artery). An abnormal heart sound during a heartbeat (heart murmur) can often be heard during a chest exam. If SVAS is not treated, the aortic narrowing can lead to shortness of breath, chest pain, and ultimately heart failure.\n\nThe severity of SVAS varies considerably, even among family members. Some affected individuals die in infancy, while others never experience symptoms of the disorder.
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.
Tetralogy of Fallot
MedGen UID:
21498
Concept ID:
C0039685
Congenital Abnormality
People with CCHD have one or more specific heart defects. The heart defects classified as CCHD include coarctation of the aorta, double-outlet right ventricle, D-transposition of the great arteries, Ebstein anomaly, hypoplastic left heart syndrome, interrupted aortic arch, pulmonary atresia with intact septum, single ventricle, total anomalous pulmonary venous connection, tetralogy of Fallot, tricuspid atresia, and truncus arteriosus.\n\nEach of the heart defects associated with CCHD affects the flow of blood into, out of, or through the heart. Some of the heart defects involve structures within the heart itself, such as the two lower chambers of the heart (the ventricles) or the valves that control blood flow through the heart. Others affect the structure of the large blood vessels leading into and out of the heart (including the aorta and pulmonary artery). Still others involve a combination of these structural abnormalities.\n\nSome people with treated CCHD have few related health problems later in life. However, long-term effects of CCHD can include delayed development and reduced stamina during exercise. Adults with these heart defects have an increased risk of abnormal heart rhythms, heart failure, sudden cardiac arrest, stroke, and premature death.\n\nAlthough babies with CCHD may appear healthy for the first few hours or days of life, signs and symptoms soon become apparent. These can include an abnormal heart sound during a heartbeat (heart murmur), rapid breathing (tachypnea), low blood pressure (hypotension), low levels of oxygen in the blood (hypoxemia), and a blue or purple tint to the skin caused by a shortage of oxygen (cyanosis). If untreated, CCHD can lead to shock, coma, and death. However, most people with CCHD now survive past infancy due to improvements in early detection, diagnosis, and treatment.\n\nCritical congenital heart disease (CCHD) is a term that refers to a group of serious heart defects that are present from birth. These abnormalities result from problems with the formation of one or more parts of the heart during the early stages of embryonic development. CCHD prevents the heart from pumping blood effectively or reduces the amount of oxygen in the blood. As a result, organs and tissues throughout the body do not receive enough oxygen, which can lead to organ damage and life-threatening complications. Individuals with CCHD usually require surgery soon after birth.
Anteriorly placed anus
MedGen UID:
333160
Concept ID:
C1838705
Finding
Anterior malposition of the anus.
Feeding difficulties in infancy
MedGen UID:
436211
Concept ID:
C2674608
Finding
Impaired feeding performance of an infant as manifested by difficulties such as weak and ineffective sucking, brief bursts of sucking, and falling asleep during sucking. There may be difficulties with chewing or maintaining attention.
Chiari malformation
MedGen UID:
2065
Concept ID:
C0003803
Congenital Abnormality
Chiari malformation consists of a downward displacement of the cerebellar tonsils and the medulla through the foramen magnum, sometimes causing hydrocephalus as a result of obstruction of CSF outflow.
Motor delay
MedGen UID:
381392
Concept ID:
C1854301
Finding
A type of Developmental delay characterized by a delay in acquiring motor skills.
Ventriculomegaly
MedGen UID:
480553
Concept ID:
C3278923
Finding
An increase in size of the ventricular system of the brain.
Mild global developmental delay
MedGen UID:
861405
Concept ID:
C4012968
Finding
A mild delay in the achievement of motor or mental milestones in the domains of development of a child.
Thrombocytopenia
MedGen UID:
52737
Concept ID:
C0040034
Disease or Syndrome
A reduction in the number of circulating thrombocytes.
Hypotonia
MedGen UID:
10133
Concept ID:
C0026827
Finding
Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist.
11 pairs of ribs
MedGen UID:
326950
Concept ID:
C1839731
Finding
Presence of only 11 pairs of ribs.
Spinal canal stenosis
MedGen UID:
396107
Concept ID:
C1861329
Anatomical Abnormality
An abnormal narrowing of the spinal canal.
Pectus excavatum
MedGen UID:
781174
Concept ID:
C2051831
Finding
A defect of the chest wall characterized by a depression of the sternum, giving the chest ("pectus") a caved-in ("excavatum") appearance.
Atopic eczema
MedGen UID:
41502
Concept ID:
C0011615
Disease or Syndrome
Atopic dermatitis (ATOD), also known as eczema, is a common chronic pruritic inflammatory skin disease with a strong genetic component. Onset typically occurs during the first 2 years of life (review by Soderhall et al., 2007). Genetic Heterogeneity of Atopic Dermatitis Many inflammatory diseases, such as atopic eczema, are genetically complex, with multiple alleles at several loci thought to be involved in their pathogenesis. Several susceptibility loci for atopic dermatitis have been identified: ATOD1 on chromosome 3q21, ATOD2 (605803) on chromosome 1q21, ATOD3 (605804) on chromosome 20p, ATOD4 (605805) on chromosome 17q25.3, ATOD5 (603165) on chromosome 13q12-q14, ATOD6 (605845) on chromosome 5q31-q33, ATOD7 (613064) on chromosome 11q13.5, ATOD8 (613518) on chromosome 4q22.1, and ATOD9 (613519) on chromosome 3p24.
Lymphopenia
MedGen UID:
7418
Concept ID:
C0024312
Disease or Syndrome
A reduced number of lymphocytes in the blood.
Polyhydramnios
MedGen UID:
6936
Concept ID:
C0020224
Pathologic Function
The presence of excess amniotic fluid in the uterus during pregnancy.
Decreased response to growth hormone stimulation test
MedGen UID:
1784655
Concept ID:
C5539399
Finding
Insufficient responses to growth hormone (GH) provocation tests. GH deficiency is defined as a serum peak GH concentration less than 10 ng/mL on provocation with a combination of at least two separate stimulation tests.
Amblyopia
MedGen UID:
8009
Concept ID:
C0002418
Disease or Syndrome
Reduced visual acuity that is uncorrectable by lenses in the absence of detectable anatomic defects in the eye or visual pathways.
Esotropia
MedGen UID:
4550
Concept ID:
C0014877
Disease or Syndrome
A form of strabismus with one or both eyes turned inward ('crossed') to a relatively severe degree, usually defined as 10 diopters or more.
Hypermetropia
MedGen UID:
43780
Concept ID:
C0020490
Disease or Syndrome
An abnormality of refraction characterized by the ability to see objects in the distance clearly, while objects nearby appear blurry.
Strabismus
MedGen UID:
21337
Concept ID:
C0038379
Disease or Syndrome
A misalignment of the eyes so that the visual axes deviate from bifoveal fixation. The classification of strabismus may be based on a number of features including the relative position of the eyes, whether the deviation is latent or manifest, intermittent or constant, concomitant or otherwise and according to the age of onset and the relevance of any associated refractive error.

Term Hierarchy

Professional guidelines

PubMed

Porras AR, Rosenbaum K, Tor-Diez C, Summar M, Linguraru MG
Lancet Digit Health 2021 Oct;3(10):e635-e643. Epub 2021 Sep 1 doi: 10.1016/S2589-7500(21)00137-0. PMID: 34481768

Recent clinical studies

Etiology

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
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
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
Sarkozy A, Digilio MC, Dallapiccola B
Orphanet J Rare Dis 2008 May 27;3:13. doi: 10.1186/1750-1172-3-13. PMID: 18505544Free PMC Article

Diagnosis

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
Zenker M, Edouard T, Blair JC, Cappa M
Arch Dis Child 2022 Dec;107(12):1073-1078. Epub 2022 Mar 4 doi: 10.1136/archdischild-2021-322858. PMID: 35246453Free 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
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
van der Burgt I
Orphanet J Rare Dis 2007 Jan 14;2:4. doi: 10.1186/1750-1172-2-4. PMID: 17222357Free PMC Article

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
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
Dahlgren J, Albertsson-Wikland K
Front Endocrinol (Lausanne) 2021;12:737893. Epub 2021 Nov 9 doi: 10.3389/fendo.2021.737893. PMID: 34858328Free PMC Article
Rodríguez F, Gaete X, Cassorla F
Front Endocrinol (Lausanne) 2021;12:691240. Epub 2021 Jun 4 doi: 10.3389/fendo.2021.691240. PMID: 34149626Free 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

Prognosis

Scorrano G, David E, Calì E, Chimenz R, La Bella S, Di Ludovico A, Di Rosa G, Gitto E, Mankad K, Nardello R, Mangano GD, Leoni C, Ceravolo G
Genes (Basel) 2023 Nov 22;14(12) doi: 10.3390/genes14122111. PMID: 38136934Free PMC Article
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
Magoulas PL, El-Hattab AW
Orphanet J Rare Dis 2012 Jan 4;7:2. doi: 10.1186/1750-1172-7-2. PMID: 22216833Free PMC Article
Sarkozy A, Digilio MC, Dallapiccola B
Orphanet J Rare Dis 2008 May 27;3:13. doi: 10.1186/1750-1172-3-13. PMID: 18505544Free PMC Article
van der Burgt I
Orphanet J Rare Dis 2007 Jan 14;2:4. doi: 10.1186/1750-1172-2-4. PMID: 17222357Free 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
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
Johnston JJ, van der Smagt JJ, Rosenfeld JA, Pagnamenta AT, Alswaid A, Baker EH, Blair E, Borck G, Brinkmann J, Craigen W, Dung VC, Emrick L, Everman DB, van Gassen KL, Gulsuner S, Harr MH, Jain M, Kuechler A, Leppig KA, McDonald-McGinn DM, Can NTB, Peleg A, Roeder ER, Rogers RC, Sagi-Dain L, Sapp JC, Schäffer AA, Schanze D, Stewart H, Taylor JC, Verbeek NE, Walkiewicz MA, Zackai EH, Zweier C; Members of the Undiagnosed Diseases Network, Zenker M, Lee B, Biesecker LG
Genet Med 2018 Oct;20(10):1175-1185. Epub 2018 Feb 22 doi: 10.1038/gim.2017.249. PMID: 29469822Free PMC Article
Magoulas PL, El-Hattab AW
Orphanet J Rare Dis 2012 Jan 4;7:2. doi: 10.1186/1750-1172-7-2. PMID: 22216833Free PMC Article

Recent systematic reviews

Debbaut E, Steyaert J, El Bakkali M
Mol Genet Genomic Med 2024 Apr;12(4):e2428. doi: 10.1002/mgg3.2428. PMID: 38581124Free PMC Article
Olwi D, Day F, Ong K
Horm Res Paediatr 2024;97(1):1-10. Epub 2023 Apr 19 doi: 10.1159/000530578. PMID: 37075730
Cox TP, Vance CJ, Daley SK, Papendieck C, McGregor H, Kuo P, Witte MH
J Vasc Surg Venous Lymphat Disord 2022 Sep;10(5):1192-1196.e3. Epub 2022 May 10 doi: 10.1016/j.jvsv.2022.03.017. PMID: 35561969Free PMC Article
Pauta M, Martinez-Portilla RJ, Borrell A
Ultrasound Obstet Gynecol 2022 Jan;59(1):26-32. doi: 10.1002/uog.23746. PMID: 34309942
Richards C, Jones C, Groves L, Moss J, Oliver C
Lancet Psychiatry 2015 Oct;2(10):909-16. Epub 2015 Sep 1 doi: 10.1016/S2215-0366(15)00376-4. PMID: 26341300

Supplemental Content

Table of contents

    Clinical resources

    Practice guidelines

    • PubMed
      See practice and clinical guidelines in PubMed. The search results may include broader topics and may not capture all published guidelines. See the FAQ for details.

    Recent activity

    Your browsing activity is empty.

    Activity recording is turned off.

    Turn recording back on

    See more...