Prosencephalon

We are all born with many things we take for granted. Properly developed brains, facial features in their correct places, and a life span longer than a few hours. Some children who are born with holoprosencephaly, or HPE, aren't quite as lucky. Victims of this disease suffer with various abnormalities to the face and brain, sometimes resulting in death. Their symptoms can range from almost normal facial features and brain development, to something most of us thought only occurred in fictional novels. When your brain is being formed it usually divides into two hemispheres, a right and a left. "To establish the line that separates the two hemispheres (the midline), the activity of many genes must be tightly regulated and coordinated. These genes provide instructions for making signaling proteins, which instruct the cells within the brain to form the right and left hemispheres." (Genetics Home.). If mutations occur within these genes it results in the production of abnormal or nonfunctioning signal proteins. Without the correct signals, the brain does not separate into two hemispheres. The mutation most commonly occurs within one of these genes: SHH, SIC2, SIX3, or TGIF1. The mutation can also be related to an abnormality of chromosomes, most commonly trisomy 13, which is when there are three copies of chromosome 13. (NORD). In some cases, it is just considered a birth defect that occurs during the early stages of pregnancy. While pregnant with a child, if the mother has…

Cyclopia is a malformation that involves a lack of splitting of the single eye field into two bilateral eye fields and is typically accompanied by a non-functioning proboscis dorsal to the eye. This malformation is typically caused by a deficiency in midline shh signaling from the brain in which there is an incomplete cleavage of prosencephalon into the left and right hemispheres which occurs sometime between the 18th and 28th day of gestation. The primary defect is the lack of forebrain tissue…

Last there is the brain. The brain is the control focal point of the human body. The human brain stores data, corresponding that data with other data to offer the body some assistance with making selections and to have the body put the decisions into actions. The brain and spinal cord are created from the neural tube. The neural tube then extends causing the tube to then makes three locales called the primary brain vesicles: prosencephalon, mesencephalon, and the rhombencephalon. The…