Write cause and characters of Edward Syndrome.
Answers
Edwards Syndrome (also known as Trisomy 18 (T18) or Trisomy E) is a genetic disorder caused by the presence of all or part of an extra 18th chromosome. The majority of people with the syndrome die during the fetal stage; infants who survive experience serious defects and commonly live for short periods of time. Edwards' syndrome is associated with a broad spectrum of abnormalities which consist of greater than one-hundred and thirty discrete defects involving the brain, heart, craniofacial structures, kidneys and stomach.
Edward's Syndrome (also known as Trisomy 18 (T18) or Trisomy E) is a genetic disorder caused by the presence of all or part of an extra 18th chromosome. It is named after John H. Edwards, who first described the syndrome in 1960.
The syndrome occurs in about one out of every five-thousand births. Edward's syndrome affects more girls than boys - around 80 percent of those affected are female. Women older than the age of thirty have a greater risk of bearing a child with the syndrome, although it may also occur with women younger than thirty. Edward's syndrome was named after Dr. John Edward.
Causes of Edward's Syndrome
Cells in the human body contain twenty-three pairs of chromosomes that are inherited from the person's parents. In human reproductive cells, ovum cells in women and sperm cells in men each have twenty-three individual chromosomes, referred to as, 'XX,' in women and, 'XY,' in men and numbered one through twenty-two. The extra material from chromosome eighteen, obtained after the egg is fertilized, is responsible for causing Edward's syndrome.
Children with Edward's syndrome have an incorrect number of chromosomes. Children with the syndrome inherit three (referred to as a, 'trisomy'), instead of two, copies of chromosome eighteen. Ninety-five percent of children with Edward's syndrome have what is referred to as, 'full-trisomies,' while two-percent are due to trans-locations where only a portion of an extra chromosome is present. Three-percent of children with Edward's syndrome have what is referred to as, 'mosaic tristomies,' where the extra chromosome is there, but not in every one of the child's cells.
Symptoms of Edward's Syndrome :
The majority of children born with Edward's syndrome appear both fragile and weak; many are underweight. Their heads are unusually small, while the backs of their heads are prominent. Their ears are low-set and malformed, and their mouths and jaws are small, a condition referred to as, 'micrognathia.' Babies with the syndrome may experience a cleft palate or lip. Their hands are often clenched into fists, with their index finger overlapping their other fingers. Babies with Edward's syndrome can have clubfeet, as well as toes that may be fused or webbed.
Children with the syndrome can experience problems with their lungs and diaphragm, and blood vessels which are malformed. They may present with a number of types of congenital heart disease, to include atrial septic defect, ventricular septal defect, or patent ductus arteriosus. Children with the syndrome might have an inguinal or umbilical hernia, abnormalities of their urogenital system, malformed kidneys, or undescended testicles if they are male.