Noonan Syndrome, also known as Turner-Like Syndrome, Noonan-Ehmke Syndrome, Ullrich-Noonan Syndrome, is a genetic ailment that restricts the healthy and regular development of tissues, organs in several regions of the body. The distinct attributes of this illness consist of irregular facial aspects, very small build, lower than normal body weight, suppressed growth of torso, limbs and damages to heart function right from birth, like in the case of Alagille Syndrome.

Also Read: Alagille Syndrome: How This Genetic Disorder Negatively Influences The Liver And Heart In Children

Noonan Syndrome

This congenital malady was first discovered in the year 1883 and is designated after the established American paediatric cardiologist Jacqueline Noonan, who, in 1963, conducted in-depth research on the underlying reasons and typical signs of this gene-related condition. Although there is no cure yet, the growth-inhibiting symptoms affect only physical facets such as height, weight and development, functions of internal organs like heart, lungs and do not hamper the intelligence, brain activity, memory of the child. This childhood sickness can be managed efficiently if the unique signs are identified and reported to the doctor immediately. If left unattended to, Noonan syndrome can result in grave lymphatic situations, heightened risk of urinary tract infections, cancers, and even decreased fertility in males owing to undescended testicles or cryptorchidism. It is hence essential to know the causes and symptoms of this genetic disease, for the accurate diagnosis and timely treatment of the afflicted child.

Also Read: Cryptorchidism: Causes, Symptoms And Treatment

Causes Of Noonan Syndrome

Noonan syndrome is triggered by faults in DNA, predominantly in the genes associated with the RAS family of proteins, that are important for the development of healthy organs and tissues. This is either due to inherited mutations, from one of the parents carrying aberrant genes that are passed on to the baby, or random mutations that form de novo i.e. beginning for the first time in the child’s system.

Since this network of genes is involved in cell proliferation, growth and division operations that form normal functional tissues, the creation of optimal, healthy organs is hindered.


The degree to which the baby is affected depends on the exact gene that is abnormal and therefore, the symptoms of Noonan syndrome can be slight at times, or even quite serious in other circumstances.

Facial features consist of eyes with droopy lids and set wider apart on the front of the head, with flattened extended noses, crooked teeth and a big head. Detrimental structures are also present in the heart, chest muscles, spinal cord, eyes as refractive errors like myopia and ear bones as in hearing difficulties.

In certain instances, very severe indications are also exhibited by the child with Noonan syndrome, including the late onset of puberty, decreased fertility capabilities, reduced immunity owing to inflamed lymph tissues as in lymphedema, uncontrolled bleeding, restricted functioning of kidneys.


The physician assesses all the external signs displayed by the patient and then analyses a sample of the genetic material. However, in the majority of cases, it is rather challenging to properly diagnose Noonan syndrome as the outward signs are very subdued in the child and become very prominent only in adulthood. When symptoms related to heart difficulties are reported, a cardiologist studies the cardiac pathways, valves and vessels, to correctly identify the disorder and provide appropriate treatment.


Currently, advanced techniques to rectify the gene defects in Noonan syndrome have not been discovered and hence a cure does not exist. Nevertheless, the symptoms linked with the genetic ailment can be remedied effectively, once they are spotted and promptly reported to a medical expert.

The healthcare provider advises prescription medications to mend all heart complications and if the stature of the child is very short, growth hormone levels are inadequate, hormonal therapy is recommended. Medicines are also prescribed to induce clotting, in situations where bleeding and bruising occur frequently. Evaluating the numerous symptoms of Noonan syndrome and resolving them through pertinent prescription drugs, hospital procedures improve physical growth, regulates organ development, hormonal synthesis and enhance the overall health of the child.