Genetic Disorder & Causes
Is an abnormal condition that a person inherits through genes and chromosomes
Two causes: Mutations In DNA, and Changes in overall structure or numbers of chromosomes
Causes of Genetic disorders
Mutations In DNA Changes in overall structure or numbers of chromosomes
Down Syndrome (Trisomy 21)
Extra chromosome 21 in every cell of the body.
Causes mental retardation, & heart defects
As a woman gets older, her chances of having a baby with a chromosome abnormality increases
female born with only one X chromosome
ovaries do not develop (infertile)
kidney and thyroid problems
• skeletal disorders such as scoliosis
Infertility (cannot produce a lot of sperm)
Abnormal body proportions (long legs, short trunk, shoulder equal to hip size)
Abnormally large breasts (gynecomastia)
Genetic disorder in which the body produces abnormally thick mucus in the lungs and intestines.
Caused by a recessive allele that is a result of a mutation in which 3 bases are deleted from a DNA molecule.
Sickle Cell Disease
Affects hemoglobin, which is a protein that carries oxygen.
When oxygen levels are low the blood cells have a sickle shape instead of the normal round shape.
These sickle blood cells clog blood vessels and carry less oxygen.
How to Manage Genetic Disorders
Karyotypes - used to detect chromosomal disorders such as down syndrome
Genetic counseling - Assess the risk of a genetic disorder by researching a family's history and evaluating medical records.
Human trait controlled by more than one allele is said to have multiple alleles
Even though a gene may have multiple alleles, a person can only carry 2 of those alleles because we have only 2 chromosomes.
Four major blood types: A, B, AB, and O
Blood Types A, B, & AB
Alleles for blood type A is AA or AO.
Alleles for blood type B is BB or BO.
a cross between blood type A and blood type B.
Results in a person with type AB blood.
Type O Blood
Allele for blood type O is recessive
Only way to get type O is to have both parents with blood type O
Advances in Genetics
Human Genome Project
Human Genome Project
Genome is all the DNA in one cell of an organism.
HGP- is the code that is 6 billion letters long.
Main goal of the project is to identify the DNA sequence of every gene in the human genome.
We have at least 30,000 genes.
Average gene has about 3,000 bases.
DNA is broken down into small fragments.
Selected fragments are used to produce a pattern called a DNA Fingerprint.
Genes from one organism are transferred into DNA of another.
Used to produce medicine and crops resistant to diseases.
Insulin (used by diabetics) is produce by genetically engineered bacteria.
Genes are inserted into animals such as cows to produce the human clotting protein needed by people with hemophilia.