genes, epigenetics, and genetic disorders

Transcription

The synthesis of mRNA from a DNA 'template' in the nucleus.

Translation

The process where ribosomes synthesize protein from mRNA.

Human Karyotype

46 chromosomes consisting of 22 pairs of autosomes and 1 pair of sex chromosomes.

Point Mutation Types

Silent, nonsense, and missense mutations.

Frameshift Mutation

A genetic mutation caused by insertions or deletions that alter the reading frame.

Cystic Fibrosis Cause

Autosomal recessive mutation causing a buildup of thick, sticky mucus in organs.

Sickle Cell Disease Cause

Mutation in both copies of the hemoglobin gene causing RBCs to deform.

Marfan Syndrome Cause

Mutation in the FBN1 gene affecting connective tissue production.

Huntington's Disease Inheritance

Autosomal dominant disorder causing progressive degeneration of brain nerve cells.

Nondisjunction

Failure of homologous chromosomes or sister chromatids to separate normally during meiosis.

Down Syndrome Karyotype

Trisomy 21

designated as 47, XX, +21

or 47, XY, +21.

Chromosome Arm Symbols

'p' designates the short arm; 'q' designates the long arm.

Epigenetics

Changes in gene expression (such as DNA methylation) without altering DNA sequence.

female karyotype nomenclature

46, XX

Male karyotype Nomenclature

46, XY

Genotype

genetic makeup

Phenotype

physical characteristics of an organism

Heterozygous

having two different alleles for a trait (Bb)

homozygous recessive

Both alleles are the same and recessive (bb)

homozygous dominant

Both alleles are the same and dominant (BB)

silent mutation

alters a base but does not change the amino acid

nonsense mutation

A mutation that changes an amino acid codon to a stop codon, resulting in a shorter and usually nonfunctional protein.

missense mutations

which mutations are known to drive evolution?

missense conservative mutation

altered codon changes the amino acid to one that is chemically similar to the original

missense non-conservative mutation

altered codon changes the amino acide to one that is chemically different from the original

darker eyes

you can withstand high glare lights better if you have ____ ____

Triploidy

when an organism has three copies of every chromsome instead of two

Turner Syndrome

A chromosomal disorder in females in which either an X chromosome is missing, making the person XO instead of XX, or part of one X chromosome is deleted.

duplication chromosomal mutation

inversion chromosomal mutation

insertion chromosomal mutation

deletion chromosomal mutation

translocation chromosomal mutation

Cri du chat syndrome

deletion of short arm of chromosome 5

1-22

autosome

X,Y

Sex chromosomes

(+) OR (-)

When placed before the autosomal number, this indicates that the chromosome is an extra or missing

cen

centromere

inv

inversion

p

short arm of the chromosome

q

long arm of the chromosome

t

translocation abbr

del

deletion abbr

ins

insertion abbr

dup

duplication abbr

dutch hunger winter famine

Exposure to famine during the _____ _____ _____ ______ caused lasting changes in DNA methylation, particularly altering genes related to growth and metabolism in individuals conceived during that period

genes =

DNA -> Protein

How are genetics and epigenetics different?

Genetics involves changes or differences in the DNA sequence. Epigenetics involves changes in how that DNA is used.

DNA methylation

The addition of small chemical tags called methyl groups to DNA, often reducing the activity of a gene.

histones

Proteins that DNA wraps around to help organize and package it.

histones effect on gene activity

If DNA is packed tightly around histones, genes are harder to read. If it is packed loosely, genes are usually easier to read.

epigenetic pattern influences

Development, aging, hormones, nutrition, smoking, stress, toxins, and other environmental factors.