I. Organell Inheritance

II. Infectious Heredity

III. Maternial Effect

• Inheritance from Chloroplast and Mitochondria
• function of organelles is dependent on gene products from nuclear and organelle DNA

• Large number of organelles are contributed to each progency in cell division.

1. Heteroplasy-mixture of organelles (wildtype and mutant)
2. Homoplasmy-uniform Mitochondrial DNA

Virus infects cytoplasm; it alters phenotype

• Ex: Yeast Double-stranded RNA L&M Virus

• nuclear gene products stored in egg
• proteins or RNA distributed throught egg after fertilization;influence on phenotype

1. Drosophilia Mutation- if progency acquires 1 wildtype allel even if it is homozygous for genotype it will not express the mutation

• Ancestral Relations
• Mitochondrial Eve
• Forensic Biologist
• Cells contain thousands of copes of MTDNA; useful when DNA sample is degraded or old
• remains of soldier
• Relationship for Neandertal to humans

Mitochondrial Genetic Disorders

• high energy demand tissue: CNS, heart
• LHON sudden blindness
• MELAS
• WOLF_
• MERRF-red fiber

Mitochondrial DNA-Woman

Nuclear DNA-Mother

Nuclear DNA Father

• Found in many cancers, Parkinson,bipolar
• can be causitive agent or consequences of disease

• possess cells with genetic difference from other cells in their body
• two different genotypes; different preiod of development

I. Somatic- affecting cells other than sperm or egg

II. Gonadal-portion of gametes will have the mutation

• AD/ X-linked
• X-linked- to prevent lethal gene dosage, one X is inactivated after fertilization. The Two X-chrosomes diffir in patterns of allels reulsting in different phenotype. Once chromosome is silenced.
• EX. Calico Cat

-Expression of genes varies depending if the mutation was inherited from the mother or father.

• New pattern of imprinting in each generation

Imprinting

I. Methylation

-male and female Pattern

-allel is silenced by addition of Methyl

-genes are expressed from nonimprinted allel in humans

II. Histone Modification

-proteins that the DNA are wrapped around

Angelman Disoder Vs Prader Willi disoder

1. Deletion of maternal chromosome vs deletion of paternial.

Chemical changes to DNA

overall egogentic state of cell

Famine-> Schizophrenia

• low caloric intake
• Chinese famine 2x schizophrenia
• low folic acid
• hypomethylation

If material mouse doesnt groom offspring, they have decreased receptors for Glucocoritcord needed for stress.

• decreased levels have been seen in suicide victiums.
• Chromic Cocaine Use can decrease histone methylation
• Drug use can effect gene expression

• Both Chromomes are inherited from the same person
• Nondisjunction in Meiosis II
• Identified by Cystic Fibrosis Patient who inherited both genes from mother
• recessove allels
• Imprinted( bother expressed or silenced)

• phenotype os more severe
• earlier onset with generation
• Triplet Repeat (AD)
• Huntingtons Disease
• Affect 30-90
• Malformed proteins in the neurons
• Repeats on coding and noncoding regions

I. Single Gene Mutation

II. Continuous Gene Deletion

III. Chromosomal Disorders

IV. Complex Disorder- genes and environment

Multifractional

I. Retinitis Pigmentosa

-loss in peripheral vision

-rods help in side and night vision and eventually stops.

-multiple genes involves

-AD, AR, X

II. Bardet-Beidel

-obesity, polydactyl

-14 different genes

-3 mutated genes for phenotype

-2 recessive mutations and 1 mutation on another gene

III. Eye Color

-Based on Melanin levels

OCA2 no protein is made results in albinism

-Additive of genetic risk factors

-Spina Bifida

-Neural tube defect

-3 types

lack of folic acid, can be rediced by 70%

• continuously varying
• quantitative
• controlled by many genes and environment
• adult onset
• higher risk to immediate family memebers, lower risl in 2nd degree relatives
• higher risk >1 more severe phenotupe
• environmental exposure

Risk

Empirical

heritiability

Adoption

Twin

Association

Sib-Ship

• incidence of trait in population by observation
• Ex 1 in 100,000
• If sibling has neural tube defect, risk is 3%
• used for genetic counceling
• identical twin 40% cleft lip
• sibling 4%

-Phenotype variation to die genetic differences in population at specific time

-Ex. Height: H=0.65, then 65% variation in height is explained by genotypic differences.

-Phenotype due to only genetic factor H=1.

sibling (1/2)

Parent(1/2)

Uncle(1/4)

Grandparents(1/4)

Cousin(1/8)

H=O/E

Concordance- Measures degree to which trait is inherited

MZ Twins: AD AR 100%

DZ AD 50% AR 25%

<100 MZ concordance due to environmental factors

SNP- compare allel frequences between affected and nonaffected individuals.

-SNP patterns, risk of developing disease, age, sex, ethnicity

• sequence change >1% population
• every 300 bases, most noncoding

• Pattern of SNP over a certain area
• closer together wont be seperated in meiosis

• identify common SNPs in genome
• differne population associations between SNPS and disorders.

• studies siblings with complex disorders
• share 50% genome
• look for SNPs that affect sib-share and correlate to disease

• Predict alzheimers
• APOE4 risk factor
• APOE2 Protective Factor
• subdivision of phenotupe