Understanding of Inheritance

Karyotyping

Studies the number and kind of chromosomes in a nucleus by matching up pairs of homologous chromosomes so researchers can identify chromosome abnormalities.

Cytogenetics

Study of chromosomes and their role in inheritance

Pedigree

A family tree that is used to examine the transmission of genetic traits over generations.

Human genome project

3.5 billion base pairs, 20,000-30,000 genes and about 1-2% of genomes code for proteins. 

Bioinformatics

Used in storing, retrieving and the comparison of DNA. can also compare organisms of different species and phylogeny. 

phylogeny

Organisms that share a common ancestor and have more similarities in their DNA sequence.

Pharmacogenetics

The study of how an individual’s genetic inheritance affects the body’s response to drugs. Can be used to make customized drugs that minimize effects.

Proteomics

Studies of proteins encoded by human genome. Can be used to determine the interactions between proteins and diseases.

Polyploidy

The presence of multiple sets pf proteins. This is common in plants but fatal in humans.

Aneuploidy

Missing or extra copies of certain chromosomes.

Trisomy 21

Down syndrome, an extra chromosome 21 results in genetic imbalance that causes physical and mental abnormalities. (occurs in 1/800 live births)

Meiotic nondisjunction

Sister chromatids or homologous chromosomes fail to move apart and cause trisomy or monosomy. (1% of all live births)

Miscarriages

17% of all pregnancies result in this and ½ pf them are a result of aneuploidy.

Translocations

Exchange of DNA from one chromosome to a nonhomologous chromosome

Reciprocal translocation

Two nonhomologous chromosomes exchange genetic information

Cri du chat

An abnormality caused by the deletion of part of chromosome 5 that affects 1/5000 live births.

Fragile site

Site where a chromatid is joined together by a thin thread of DNA.

Phenylketonuria (PKU)

Common in western European descent, effects 1/10,0000 live births,1 in 50 are carriers and cause an accumulation of phenylalanine. Can be identified in newborns and combated by regulation of P think in one’s diet.

Sickle cell

Occurs in 1/500 AA (1 in 12 are carriers) and is caused by a mistake in 1 protein that makes up the hemoglobin molecule. Blocks blood vessels due to lack of oxygen causing them to die early.

Tay-Sachs disease

Occues in people of Eastern Euro and Ashkenazi Jewish descent (1 in 27 Jewish ppl in the US are carriers). Causes a buildup of fatty materials in the nerve cells that diminishes physical and mental abilities in the child. Death usually by age 4 and screening is available. 

Cystic fibrosis

Most common in whites (1 in 30 are carriers) causes a thick sticky mucous which can block the lungs and repeated infections. There is no cure but treatment and screening is available. 

Huntington’s disease

Occurs in 1/20,000 and if your parent has it you have a 50% of having it. Causes deterioration pf part of your brain that creates mood changes coordination deterioration, uncontrolled muscle spasms and death. 

Gene therapy

Normal allele is cloned; DNA is introduced into certain body cells and then a virus is used to insert the correct copy of the gene into cells that are producing the incorrect protein. 

Amniocentesis

0.5% chance of miscarriage and is used to detect down syndrome, spina bifida and many other genetic disorders.

Chronic villus sampling

Earlier results that amniocentesis but greater risk of infection and miscarriage.

Preimplantation genetic dignosis

Screens embryos prior to being implanted and can be used to detect genetic disorders without any risks.