New Research Provides Hope for Down Syndrome Patients
We know how hard it is to be a parent to a child with Down’s syndrome. Being a parent to this special child can be a huge physical and emotional challenge for you and for the other members of your family. But it helps to hear that you are not alone in your daily challenges.
There is no treatment or method of prevention for Down’s syndrome, though some health problems that come with it can be treated. However, a new study has found out one molecular mechanism behind this disease, creating a possibility for treatment discoveries.
In this study published in Nature Medicine, scientists from California have found out that there is a connection between Down’s syndrome and a protein called SNX27 (sorting nexin 27). This protein regulates certain receptors in the surface of nerve cells. These receptors are known as glutamate receptors and they facilitate communication between cells through a neuromediator called glutamate. Glutamate transmits nerve signals from one nerve cell to another.
Glutamate receptors respond to the presence of glutamate molecules in a specific manner. If glutamate receptors are lesser in amount than normal, there is lesser communication among nerve cells and this result to impairment of cognitive function. This is what happens in Down’s syndrome. In people with Down’s syndrome, protein SNX27 levels are lower compared to that of normal people. The investigators of this study have also discovered that chromosome 21 carries a gene which has a certain substance that decreases the production of SNX27 in neurons.
In this particular study, mice with Down’s syndrome were studied. The experts were able to demonstrate that if the production of the inhibitory compound affecting SNX27 levels is blocked, normal brain and nerve function may return. The investigators then blocked the production of SNX27 in neurons through gene therapy. With these findings, there is a possibility that cognitive impairment in humans with Down’s syndrome can be effectively treated with gene therapy.
Indeed this is good news for parents who have children with Down’s syndrome. Hopefully, gene therapy can be done in actual human patients in the near future so that patients with Down’s syndrome can have improvement in cognitive function and can effectively function in society.
Image from http://www.cdc.gov/ncbddd
According to the Centers for Disease Control (CDC), one of every 800 babies born in the United States every year has Down’s syndrome. These babies are born with an extra copy of chromosome 21, a fact which makes them special.
Down’s syndrome, also called Trisomy 21, can lead to various problems, both mentally and physically. It can cause delays in child development and physical symptoms such as poor muscle tone, a flattened nose, a flat face, a short neck, excess skin at the back of the neck, small head and small ears and mouth. Other physical attributes of these patients include an upward slanting of the eyes, white spots on the colored part of the eyes, short hands with short fingers, a single deep crease on the palm of the hand and a deep groove located in between the first and second toes. These physical characteristics can cause isolation and humiliation for the patient so that his or her emotional health is affected.
In terms of intellectual development, children with Down’s syndrome often have mild to moderate cognitive problems. These children may have a short attention span, poor judgement, slow learning, impulsive behaviour, and delayed language or speech development. Other problems may include heart defects, vision problems, hearing loss, infections, hypothyroidism, blood disorders, problems with the spine, poor muscle strength and tone, disturbed sleep, gum and teeth problems, epilepsy, digestive problems and various mental and emotional problems.
US Department of Health and Human Services National Institutes of Health. Down Syndrome: Condition Information (2012). Retrieved June 20, 2013 from http://www.nichd.nih.gov/health/topics/down/conditioninfo/Pages/symptoms.aspx
Jones MW. Sorting receptors at Down’s syndrome synapses. Nat Med. 2013 Apr;19(4):404-6.