By: Mary Sakacs


Why does one child have green eyes and the other have blue? It’s all in the genes. When we think about genetics, features like hair color, height, and facial appearance are usually what come to mind first. But genetics goes deeper than that. The genes we inherit from our family make-up a lot of who we are, and sometimes that’s not a good thing.


Every cell contains between 25,000 and 35,000 genes, but just one can have a negative affect on your life, and I don’t mean inheriting your mother’s obnoxious laugh. Due to certain faulty genes, children can be born with diseases or illnesses that they inherited from specific genes. Today, scientists are determined to uncover what genes cause such affects.


A recent breakthrough found in a study by the Centre for Addiction and Mental Health, proved that a specific gene links to intellectual disability in those who may carry it. After observing five families with children who have intellectual disability, Senior Scientist John Vincent, PhD along with his colleague’s discovered defects on the gene, MAN1B1.


Vincent’s study was published in the July issue of the American Journal of Human Genetics. His study shows that all twelve children from these five families proved to have two copies of a defective MAN1B1 gene that they had inherited from each of their parents. While they were all composed of different types of mutations on the gene, the aftermath was the disability in each child’s case. This verifies that it was due to this gene that the child obtained the disability.


The cause of defective genes, according to Vincent, is how the enzyme manages the functioning of cells. The enzyme is supposed to manage the proteins created in cells and remove damaged ones in order to prevent them from being released into the body. However with the defective gene MAN1B1, this does not take place.


Originally the team had done a similar study on four families in Pakistan with whom many had intellectual disability. This first study was the beginning of the process in mapping possibly dangerous genes. By teaming up with the Max Planck Institute of Berlin, Germany and using next-generation sequencing, CAMH discovered the MAN1B1 gene.


In Iran, a similar study had been conducted by the Max Planck Institute. They were able to identify the MAN1B1 gene, and this was helpful to Vincent and his team.


Vincent reports that while this gene links to intellectual disability, it is probably not the only one out there. Therefore he will further continue studies in order to detect what other genes may be harmful.


While the search for faulty genes is still on, the real question is will scientists find a way from preventing these genes from corrupting functions in the human body, or find a way to repair them before they do?


Mary Sakacs is a student at Fairleigh Dickinson University majoring in Communications studies. She is currently an editorial intern at Bioscience Technology.