Chromosomal Diseases

Amanda Labrado Biology 110 Linton Bowie Write up No. 2 10/28/09 Chromosomal Diseases The average human being has forty-six pairs of chromosomes, or twenty-three from their mother and twenty-three from their father; twenty two, from both the mother and the father,are autosomes while the remainder is the sex chromosome, X or Y. The number forty-six is significant to the number of chromosomes because when a cell is given more or less than forty-six chromosomes an embryo will be produced that may develop into an abnormal baby and/or be miscarried. Also significant to the chromosome is its shape and structure; A chromosome can sometimes be deleted, duplicated, inverted, misplaced or exchanged with part of another chromosome resulting in growth, development and health defects. Some of the most common chromosomal diseases are Down syndrome, Edward Syndrome, Turner Syndrome, and Klinefelter syndrome. Down syndrome is caused by an extra chromosome 21 so that in total there are three. Those born with Down syndrome has similar facial features such as a flattened nose arch, almond shaped eyes, light colored spot in eyes, a small mouth, small ears and a somewhat rounder face than those of the same ethnicity. People with Down syndrome suffer from slight to severe retardation. Like Down syndrome, Edward’s syndrome is caused by an extra chromosome, that is, in addition to chromosome 18. Edward’s syndrome is more common at 1 to every 3,000 births compared to 1 in every 800 for Down syndrome. Only 5% of babies born with Edward’s live past one week but some continue living until they are teenagers, but with many disabilities. People with Edward’s syndrome often have similar characteristics such as a small, oddly shaped head, a small jaw, a small mouth, low-set ears, and clenched fists with overlapping fingers. Both Down Syndrome and Edward’s syndrome can occur in either sex, male or female. Two common chromosomal conditions that can only occur in one gender are Turner Syndrome and Klinefelter’s Syndrome. Turner Syndrome appears in 1 out of every 2500 births and only occurs in females. Girls with Turner syndrome lack a second X chromosome; Symptoms of Turner syndrome are a “webbed” neck, a shield like chest area, short stature, and sometimes underdeveloped or delayed sex organs; Some women with Turner’s are incapable of reproducing. The majority of women with Turner’s Syndrome live full, healthy, lives. Equivalent to a Turner’s syndrome for men, Klinefelter’s syndrome is when a male has two X chromosomes instead of one making them XXY. Klinefelter’s appears in 1 of every 500 births but many boys born with this do not have symptoms. Men with Klinefelter’s syndrome typically are taller than average, have wide hips, are quiet in their disposition, have less facial

and body hair, are less muscular, may have larger breasts, and have a lower energy level than regular men and boys. Furthermore, 95% of Klinefelter’s are infertile because they do not produce much sperm and are more susceptible to certain diseases such as breast cancer, and vein diseases.

Works Cited "CHANGES TO CHROMOSOMES ? NUMBER, SIZE AND STR." Genetics.com. Centre for Genetics Education. Web. 28 Oct. 2009. . "Chromosomal Abnormalities - March of Dimes." Pregnancy, Babies, Prematurity - March of Dimes Foundation. Web. 28 Oct. 2009. . "Chromosome changes." Web. 28 Oct. 2009. . "Edwards Syndrome - Pregnancy or Infant Loss Due to Trisomy 18 Edwards Syndrome." Miscarriages - Pregnancy Loss and Miscarriage Symptoms. Web. 28 Oct. 2009. . "Edward's syndrome." Bio-Medicine - latest biology and medical news/technology. Web. 28 Oct. 2009. . "Features, Characteristics and Symptoms of Down Syndrome - What are the Symptoms and Features of Down Syndrome?" Down Syndrome Information on Causes, Care and Resources for Down Syndrome Families. Web. 28 Oct. 2009. . "Klinefelter Syndrome Causes, Symptoms, Diagnosis, and Prognosis Information on MedicineNet.com." Web. 29 Oct. 2009. . "Klinefelter Syndrome." NICHD - The Eunice Kennedy Shriver National Institute of Child Health and Human Development Official Home Page. Web. 29 Oct. 2009. . "Trisomy 18." Google Health. Web. 28 Oct. 2009. . "Turner Syndrome Complications and Side Effects." Turner Syndrome: Symptoms, Treatment & Complications. Web. 28 Oct. 2009. . "Turner syndrome." Google Health. Web. 29 Oct. 2009. .