Karyotyping Does it all add up?

Karyotype: a picture of paired chromosomes Match chromosomes basted on: –Size; biggest pair is pair 1; smallest is pair 22 –and banding pattern (staining pattern) First 22 pairs of chromosomes are called autosomes Last pair of chromosomes are called the sex chromosomes. –Determine gender. XX are females and XY are males.

Arrange chromosomes by size; biggest to smallest autosomes

How do you get the chromosomes to know? Blood samples Amniocentesis

Amniocentesis

Amniocentesis First remove cells Culture/grow cells Find cells going through mitosis: metaphase. Why? Stain chromosomes Take picture Pair up chromosomes; count. Normal? Abnormal? Inform parents. Counsel parents.

Cri-du-chat This syndrome is caused by a deletion of the end of the short (p) arm of chromosome 5. Found in people of all ethnic backgrounds, more common in females by a 3-1 ratio. Abnormal rate of growth of the larynx-- The cry is said to have a cat like quality, which is how the syndrome got the name "cry of the cat." Unusual facial features: microcephalic (small head size). They do not grow and develop at a normal rate. Hypotonia or poor muscle tone often inhibits the development of eating habits. About 30% of all children suffer from congenital heart defect. All patients with cri du chat show signs of mental retardation.

Cri-du-chat

Cri-du-chat karyotype

Down’s Syndrome The result of an extra copy of chromosome 21. People with Down syndrome have 47 chromosomes. Down syndrome affects 1:700 children and alters the child's phenotype either moderately or severely: characteristic facial features, short stature; heart defects susceptibility to respiratory disease, shorter lifespan prone to developing early Alzheimer's and leukemia often sexually underdeveloped and sterile, usually some degree of mental retardation. Down Syndrome is correlated with age of mother but can also be the result of non-disjunction of the father's chromosome 21.

Down’s Syndrome

Different forms; trisomy (3) of 21 st chromosome

Philadelphia translocation

Philadelphia chromosome or Philadelphia translocation is a specific chromosomal abnormality that is associated with chronic myelogenous leukemia (CML). It is the result of a reciprocal translocation between chromosome 9 and 22 chromosomalchronic myelogenous leukemiatranslocation chromosomalchronic myelogenous leukemiatranslocation 95% of people with CML have this abnormality

Philadelphia translocation

Tuner’s syndrome Common symptoms of Turner syndrome include: Short stature LymphedemaLymphedema (swelling) of the hands and feet Broad chest (shield chest) and widely spaced nipples Lymphedema Low hairline Low-set ears Reproductive sterility Rudimentary ovaries AmenorrhoeaAmenorrhoea, or the absence of a menstrual period Amenorrhoea Increased weight, obesity Shield shaped thorax of heart Shortened metacarpal IV metacarpal IVmetacarpal IV Small fingernails

Turners Syndrome

Turner’s Syndrome

Klinefelter’s syndrome Don't make as much of the male hormone testosterone Teenagers with Klinefelter's syndrome may have less facial, body hair, may be less muscular By adulthood, XXY males look similar to males without the condition, although they are often taller. They are also more likely than other men to have certain health problems, such as autoimmune disorders, breast cancer, vein diseases, osteoporosis, and tooth decay. autoimmunebreast cancerosteoporosistooth autoimmunebreast cancerosteoporosistooth

Klinefelter’s Syndrome

Jacobs Males affected with XYY are: sometimes taller than average sometimes taller than average increased risk of learning disabilities and delayed speech and language skills. learning disabilities Developmental delays and behavioral problems have also been documented, but these characteristics vary widely among affected boys and men. Most males affected with XYY have normal sexual development and are able to conceive children. About 1 in 1,000 males worldwide are affected with 47, XYY syndrome.

Jacob’s syndrome

Triple X chromosome females. 1:1000 live births - healthy and fertile - usually cannot be distinguished from normal female except by karyotype

Edward’s Syndrome

Individuals with trisomy 18 often have: a low birth weight; a small, abnormally shaped head; a small jaw and mouth; clenched fists with overlapping fingers; heart defects; and abnormalities of other organs. Due to the presence of several life-threatening medical problems, many infants with trisomy 18 die within their first month. Five percent to 10 percent of children with this condition live past their first year. Most cases of trisomy 18 are not inherited, but occur as random events during the formation of eggs and sperm.

Patau Syndrome

Serious eye, brain, circulatory defects as well as cleft palate. 1:5000 live births. Children rarely live more than a few months. Complications begin almost immediately. Complications may include: congenital heart disease. Breathing difficulty or lack of breathing (apnea) Deafness Feeding problems Heart failure Seizures Vision problems