Chromosomes

disadvantage of using the FISH technique is that only 10 to 12 chromosomes can be analyzed at a time, while a human cell contains 46 chromosomes. This lessens the chances of transferring a healthy embryo to the mother’s womb, because some mutated chromosomes might not have been discovered (“PGD/PDS”). However, this technique would be useful for Huntington’s disease because the CAG repeats that cause the disease are only located on chromosome 4 (HD). Along with preventing inherited diseases…

and an amazing team of geneticists discovered it in 1958. Down syndrome’s most common form is Trisomy 21 which is caused by a chromosomal abnormality called nondisjunction. More than 90% of the time Down syndrome is caused by an extra copy of chromosome 21…

reproduces many offspring and the offspring are created in a very fast fourteen-day cycle. The mutations are easy to identify because the traits that are affected are noticeable. (1) It contains only a few chromosomes. The only ones that contain a significant amount of genetic information are chromosomes two, three, and X. The female…

Barbra McClintock was born June 16, 1902, in Hartford, Connecticut (Editors). The third of four children born to physician Thomas McClintock and wife Sarah, McClintock was christened Eleanor, though her parents soon began to call her Barbra believing the nickname better suited her pragmatic demeanor (“Barbra McClintock”). Barbra demonstrated an interest in science from a young age, perhaps influenced by her father’s profession (Editors). At the age of seventeen, she graduated from high school…

Sperm containing the Y chromosome with a properly functioning SRY gene determines male gender, and if contains the genetic material of the X chromosome is shaped female. The presence of the SRY gene is the basic criterion of gender gene in humans. Discovered in 1990 by a group of P. Goodfellow from the University of Cambridge ,SRY gene is called the "central switch of the masculinity" and is located on the short arm of the Y chromosome locus…

Trisomy X Trisomy x syndrome, also known as triple x and 47xxx, is characterized by the presence of an extra x chromosome in each cell of a female. Three x chromosomes are present, rather than a normal pair in the nuclei of body cells. The first published report of a women with triple x syndrome was Patricia A. Jacobs at Western General Hospital in Edinburg, Scotland, in 1959. The condition occurs in about 1 in 1,000 newborn girls. Five to 10 girls with triple x syndrome are born in the united…

processes and qualities allowing the cell cycle to operate effectively and efficiently. During the cell cycle, four stages occur known as G1 phase, S phase, G2 phase, & M phase. The G1 phase is where the cell is assigned to enter the process for chromosome duplication. DNA replication occurs in the S phase. The third phase, G2 phase, the process of mitosis triggering the alignment of the mitotic spindles. Mitosis and cytokinesis are two important functions that occur throughout the M phase. The…

CHROMOSOME SYNDROMES 14 What is RING14 syndrome? RING 14 indicates an aberration with respect to chromosome 14, which takes the form of a ring as soon as its two extremities, the long arm and the short arm, fuse together. The fusion occurs through two ruptured events, one at the extremity of the short arm and the other at the end of the long arm, which usually leads to a partial loss of the informative genetic materil of chromosome 14. The chromosomal abnormality can…

anaphase, and telophase. Mitosis is comprised of prophase, metaphase, anaphase, and telophase. In prophase chromosomes compact and coil, each chromosomes consists of a pair of sisters. In this phase the nucleolus disappears and stops making ribosomes. The second stage is metaphase. This is a very brief stage and it's where all the chromosomes line up in the middle of the cell and each chromosomes attaches to a spindle fiber at its chromere. The…

Introduction Children, adolescents and adults suffer from a mental and physical disorder known as Down syndrome. This disorder is due to an extra chromosome in their genes which is the leading cause. However, a specific chromosome can also be damaged during cell replication, which can also increase their risk of getting Down syndrome and other disorders later on in their life that could eventually lead to death if not treated at the right time. Also, if a mother gives birth at a higher age, it…