Source: http://www4.nas.edu/beyond/beyonddiscovery.nsf/web/gene2

Advances in Genetic Research That Led to Gene Testing

Advances in Genetic Research That Led to Gene Testing

1860-1865 Gregor Mendel conducts his pea-breeding experiments that show how physical traits, such as height and color, are passed from one generation to the next through genes.

1944 The studies of Oswald Avery, Colin MacLeod, and provided the first experimental evidence that DNA transmits genetic information.

1953 Using an x-ray pattern of DNA generated by Rosalind Franklin, Maurice Wilkins, James Watson and Francis Crick publish their double-helix model DNA.

1960-1966 Marshall Nirenberg, Har Gobind Khorana, and their colleagues decipher the genetic code that all living cells use to translate the series of bases in their DNA into instructions for the production of proteins.

1970 Hamilton Smith discovers the first restriction enzyme that cuts DNA at specific sites. Daniel Nathans uses such restriction enzymes to generate the first physical map of a chromosome.

1973 Researchers begin to use genetically altered bacteria to clone DNA sequences.

1977 Walter Gilbert and Allan Maxam, and Fred Sanger working separately, develop techniques for rapidly "spelling out" long sections of DNA by determining the sequence of bases.

1975 Edward Southern develops a method, known as Southern blotting, to pinpoint a specific genetic sequence.

1978 Yuet Wai Kan and Andree-Marie Dozy discover restriction-fragment-length polymorphisms (RFLPs).

1985-1990 Kary Mullis and his colleagues develop a technique, called the polymerase chain reaction (PCR), for quickly amplifying and thereby detecting a specific DNA sequence.

1986 The first disease gene detected by positional cloning is identified, that for an immune disorder called chronic granulomatous disease.

1992 Building on work of Paul Modrich on understanding the DNA mismatch repair mechanisms in bacteria, Richard Kolodner and colleagues isolate a gene called MSH2 that functions in yeast mismatch repair.

1993 Bert Volgelstein and Kolodner discover that defects in the human MSH2 gene are responsible for hereditary nonpolyposis colorectal cancer (HNPCC).

SKY=Spectral KaryotypingSKY=Spectral Karyotyping

Some Currently Available Some Currently Available DNA-Based Gene Tests DNA-Based Gene Tests

Alpha-1-antitrypsin deficiency (AAT; emphysema and liver disease)

Amyotrophic lateral sclerosis (ALS; Lou Gehrig's Disease; progressive motor function loss leading to paralysis and death) Alzheimer's disease* (APOE; late-onset variety of senile dementia)

Genetic screening is now available for breast,ovarian, colon, prostate and some skin cancers.

Gaucher disease (GD; enlarged liver and spleen, bone degeneration) Inherited breast and ovarian cancer* (BRCA 1 and 2; early-onset tumors of breasts and ovaries) Hereditary nonpolyposis colon cancer* (CA; early-onset tumors of colon and sometimes other organs) Charcot-Marie-Tooth (CMT; loss of feeling in ends of limbs) Congenital adrenal hyperplasia (CAH; hormone deficiency; ambiguous genitalia and male pseudohermaphroditism) Cystic fibrosis (CF; disease of lung and pancreas resulting in thick mucous accumulations and chronic infections) Duchenne muscular dystrophy/Becker muscular dystrophy (DMD; severe to mild muscle wasting, deterioration, weakness) Dystonia (DYT; muscle rigidity, repetitive twisting movements) Fanconi anemia, group C (FA; anemia, leukemia, skeletal deformities) Factor V-Leiden (FVL; blood-clotting disorder) Fragile X syndrome (FRAX; leading cause of inherited mental retardation) Hemophilia A and B (HEMA and HEMB; bleeding disorders) Huntington's disease (HD; usually midlife onset; progressive, lethal, degenerative neurological disease) Myotonic dystrophy (MD; progressive muscle weakness; most common form of adult muscular dystrophy) Neurofibromatosis type 1 (NF1; multiple benign nervous system tumors that can be disfiguring; cancers) Phenylketonuria (PKU; progressive mental retardation due to missing enzyme; correctable by diet) Adult Polycystic Kidney Disease (APKD; kidney failure and liver disease) Prader Willi/Angelman syndromes (PW/A; decreased motor skills, cognitive impairment, early death) Sickle cell disease (SS; blood cell disorder; chronic pain and infections) Spinocerebellar ataxia, type 1 (SCA1; involuntary muscle movements, reflex disorders, explosive speech) Spinal muscular atrophy (SMA; severe, usually lethal progressive muscle-wasting disorder in children) Thalassemias (THAL; anemias - reduced red blood cell levels) Tay-Sachs Disease (TS; fatal neurological disease of early childhood; seizures, paralysis) [3/99]

DNA Forensics: Paternity

Shown at the right are DNA "fingerprints" f rom anew mother (M, Fern LaPlante), her recently bornchild (C), and two possible f athers (F1, Ross andF2, Rick). As is to be expected, the mother andthe child share a few DNA bands since they alsoshare 50% of their genes but they each havebands that are not represented among the bandsof the other.

I t is clear that the two possible f athers havedissimilar DNA banding patterns. The question isdoes one of the possible fathers have severalbands similar to the child which are not sharedwith either the mother or the other possiblefather. What do you think - was it Ross (F1) orwas it Rick (F2)?

http:/ / www.people.virginia.edu/ ~rjh9u/ forenspt.html

Blackett Family DNA Activity

http://www.biology.arizona.edu/human_bio/activities/Blackett/introduction.html