Chromosomes common in both genders
This disease is a mitochondrial disease that affects many body systems, particularly brain and nervous system, and muscles.
– Stroke and dementia – Lactic acidosis
Mitochondrial encephalomyopathy, lactic acidosis, and
stroke-like episodes (MELAS)
Example of X-linked Recessive Disease.
Duchenne Muscular Dysterophy
Turner Syndrome Characteristics
45, XO karyotype
Female (no Y)
Ovarian hypofunction/premature Ovarian failure- require hormone therapy
Most are infertile
~30% webbed neck
Low hairline on neck
CV defects (coarctation of aorta, bicuspid aortic valve)
Is pyloric stenosis more common in men or women?
Men, they need less risk genes.
Children born of affected males are less likely to get it as well.
Multiply individual probabilities for "and"
Add for "or"
When environmental factors cause variation
in the trait, the term ______ is used
Process by which monosomy and trisomy occur.
Meiosis reduces the total number of chromosomes by ___ producing ____ number of haploid gametes
Order and nomenclature is divided into how many sections
Arm P / Q
Region 2 / 1
Band 1,2,2 / 1,2,3,4
Subbands 321,21,54321 / 3,123,1234.123
Describe the structure of mitochondrial DNA
16,569 bp, double stranded, circular
The frequency at which a gene manifest itself is called _____.
Klinefelter Syndrom Characteristics
– Some with no/limited symptoms
– Varying degrees of cognitive, social,behavioral, learning difficulties
– Primary hypogonadism (low T)
– Small and/or undescended testes
– Tall stature
– Can be mosaic
– Variability in X numbers can increase
symptoms (48, XXXY; 49, XXXXY)
Name the phases in order for mitosis
Phase of Mitosis at which one copy of each chromosome (chromatid) and 1/2 of cytoplasm/organelles are distributed between the two daughter cells
Law of Independent assortment in Mendelian Genetics
Genes are inherited independently of one another
What is Trisomy 21?
Downs syndrom (47, XX + 21)
Most common trisomy
Inreased risk with maternal age
Can also occur due to translocation 46, CU
Multifactoral diseases that due not show a phenotypic bell curve have an underlying ________. In order for disease to become present they must pass the _________.
Threshold of liability
X-Linked Dominant Disease
Very rare; No carriers
Low phosphorus in blood due to defective reabsorption of phosphate in kidney due
Deficient absorption of calcium in intestine causing sofenting of bone (Rickets)
Vitamin D metabolism abnormal
How are genomic imprints passed down?
Epigenetic imprints remain throughout the lifespan of somatic cells.
In germ cells, epigentic imprints are reset at each generation.
Normal number of chromosomes
Paternal deletion of region of chromosome 15
Prader Willie Syndrome
Short stature, hypotonia, small
hands/feet, obesity, mild to moderate
What makes multifactoral inheretance recurrent risk more likely?
More then one family member affected
Expression is more severe
Less commonly affect proband is more likely to pass on
More related the parents = Higher chance
Disease example given for Reduced penetrance
autosomal dominant inheritance
Phenotype occurs in 90% of individuals inheriting gene
Name the stages of meiosis in order
One round of DNA replication
two rounds of nuclear division
Prophase I => Metaphase I => Anaphase I => Telophase I => Metaphase II => Anaphase II
Disease example of Locus Heterogeneity.
Brittle-bone disease – Mutations in collagen genes (two loci: chromosome 7 and 17), either mutation exhibits the same phenotype
Hardy Weinberg Principles
p + q = 1
Condition in which cells from a patient have different genotypes. List three examples of disease.
What is the Down's Syndrome Karyotype?
Some 46XX, some 47XX, +21
What is Trisomy 18?
47, XX +18; Edwards Syndrome
– Abnormal development
– Most perinatal death within 1 year (10% of
live births survive to 10 y.0.)