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BIMM 110. Molecular Basis of Human Disease Lecture Notes
Lecture 1: Diseases, Genes, and Chromosomes
A. Human and Human Diseases
• Purpose of Human Life: prolong life, cure diseases, and reduce suffering.
• Disease: abnormal condition that impairs bodily functions, associated with
specific symptoms and signs.
o Human disease can be caused by pathogens toxic substances,
malnutrition, and internal dysfunctions.
• Human diseases can be genetically or non-genetically related.
B. Human Genetic Disease
• Diseases mainly due to abnormalities of the genome.
• Familial Diseases: types of illness are run in families. The same disease is
noticed in different generations of the same genetically associated family
members without a clear environmental factor.
• Sporadic Diseases: types of illness appear in scattered or isolated instances
without any genetic association to other family members.
C. Genetics
• Phenotype: appearance of a feature (trait) of an individual
• Gene: unit of heredity, segment of DNA that provides the coded instructions
for synthesis of RNA -> regulate cell functions or towards translation for
proteins
• Genotype: two different allele of the same gene particular gene of interest in
diploid cells as a combination of alleles (heterozygous or homozygous)
F. Phenotype: Wet or Dry Ear Wax
• Gene: ABCC11 (ATP-Binding Cassette Subfamily C)
o One amino acid changed gives a genotype wet or dry.
o Genotype: Guanosine, Phenotype: wet
o Genotype: Adenosine, Phenotype: dry
G. Contributions in Environment Affect the Phenotype
• Ex) Flamingo Red Vs. White
o Pinkness of flamingos is not encoded into their genotype
o Food Consumed -> phenotype white or pink
o Human Perspective: skin color through sun exposure.
H. Chromosome Organization (24 Human Chromosomes)
• Longest Autosomal Chromosome: Chromosome 1
• Shorted Autosomal Chromosome: Chromosome 22
o 22 pairs autosomes and 2 pairs of sex chromosomes (XY & XX)
• Normal Cell: 23 pairs of chromosomes
I. Karyotype
• Complete set of chromosomes of a cell, including the number and
appearance of chromosomes
o During karyotyping analysis, the chromosomes are arranged and
displayed in a standard format: in pairs, ordered by size.
o Ex) Trisomy 21—Down Syndrome, an extra chromatid.
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J. Human Genome
• Human genome is stored on 23 pairs of chromosomes in each cell
o 22 pairs are Autosomal Chromosomes + 1 pair of sex chromosome
• Majority of genome contains RNA genes, regulatory sequences, and “junk”
DNA.
o Chromosome 1 contains most numbers of genes. Y contains least
number of genes
• Some genes are larger in size but contain smaller in number of genes and vice
versa
K. Characterizing Human Chromosomes
• Centromere: divides chromosome into two arms: p & q.
o P (petite): short arm
o Q: long arm
• Autosomal Chromosomes Numbering: based the length
• Staining Chromosomes: stain to provide further identity of each
chromosome.
L. Staining Chromosomes
• Regions: starting from the centromere.
• Bands: within each region are numbered in order from the centromere to
the end of each arm
• Terms for Position: band, sub-bands, sub-sub-bands
o The numbering always goes from the centromere to the end of p or
q arms.
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M. Chromosomal Location of a Gene
• Ex) CFTR
o Chromosome 7 & Long Arm Q Region #3
o Chromosomal Location: 7 q 31.2
• When solving these problems… 1st. draw the centromere, add the p and q arms.
Label regions 1, 2, 3 of your choice, within whichever region you decide which is
band 1, 2, 3.
N. Chromosome Abnormalities (Number Or Structure)
• Number Alterations:
o Aneuploidy: the change of total chromosome number, having an extra or
missing chromosomes (gain or loss).
• Structure Alterations:
o Terminal deletion, interstitial deletion, insertion, inversion, reciprocal
translocation
• Ex) Chromosome 21, Trisomy—Down Syndrome, an additional chromosome.
O. Interstitial Deletion
• The X-chromosome from the p arm region 1 and band 1 and sub-sub-band until
region 2 band 2 and sub-band 1.
o Normal chromosome is broken in two places producing 3 fragments. The
central one is lost and the outer two pieces reattach
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Lecture 2: Cell Cycle Human Disease Pedigree and Hemophilia
A. Cell Proliferation
Via Cell Cycle
• Cell Proliferation:
increase in the number of cells as a result of cell growth and division—
Mitosis and Meiosis
• Somatic Cells: cells that do no produce gametes
o Normal human somatic cells are diploid with 23 pairs of
chromosomes (2N)
• Meiosis: special cell division of germ-line cells generates sperm/unfertilized
eggs (gametes).
o Gametes are haploid with 23 chromosomes (1N)
B. Mitosis
BIMM 110. Molecular Basis of Human Disease Lecture Notes
Lecture 1: Diseases, Genes, and Chromosomes
A. Human and Human Diseases
• Purpose of Human Life: prolong life, cure diseases, and reduce suffering.
• Disease: abnormal condition that impairs bodily functions, associated with
specific symptoms and signs.
o Human disease can be caused by pathogens toxic substances,
malnutrition, and internal dysfunctions.
• Human diseases can be genetically or non-genetically related.
B. Human Genetic Disease
• Diseases mainly due to abnormalities of the genome.
• Familial Diseases: types of illness are run in families. The same disease is
noticed in different generations of the same genetically associated family
members without a clear environmental factor.
• Sporadic Diseases: types of illness appear in scattered or isolated instances
without any genetic association to other family members.
C. Genetics
• Phenotype: appearance of a feature (trait) of an individual
• Gene: unit of heredity, segment of DNA that provides the coded instructions
for synthesis of RNA -> regulate cell functions or towards translation for
proteins
• Genotype: two different allele of the same gene particular gene of interest in
diploid cells as a combination of alleles (heterozygous or homozygous)
F. Phenotype: Wet or Dry Ear Wax
• Gene: ABCC11 (ATP-Binding Cassette Subfamily C)
o One amino acid changed gives a genotype wet or dry.
o Genotype: Guanosine, Phenotype: wet
o Genotype: Adenosine, Phenotype: dry
G. Contributions in Environment Affect the Phenotype
• Ex) Flamingo Red Vs. White
o Pinkness of flamingos is not encoded into their genotype
o Food Consumed -> phenotype white or pink
o Human Perspective: skin color through sun exposure.
H. Chromosome Organization (24 Human Chromosomes)
• Longest Autosomal Chromosome: Chromosome 1
• Shorted Autosomal Chromosome: Chromosome 22
o 22 pairs autosomes and 2 pairs of sex chromosomes (XY & XX)
• Normal Cell: 23 pairs of chromosomes
I. Karyotype
• Complete set of chromosomes of a cell, including the number and
appearance of chromosomes
o During karyotyping analysis, the chromosomes are arranged and
displayed in a standard format: in pairs, ordered by size.
o Ex) Trisomy 21—Down Syndrome, an extra chromatid.
, 2
J. Human Genome
• Human genome is stored on 23 pairs of chromosomes in each cell
o 22 pairs are Autosomal Chromosomes + 1 pair of sex chromosome
• Majority of genome contains RNA genes, regulatory sequences, and “junk”
DNA.
o Chromosome 1 contains most numbers of genes. Y contains least
number of genes
• Some genes are larger in size but contain smaller in number of genes and vice
versa
K. Characterizing Human Chromosomes
• Centromere: divides chromosome into two arms: p & q.
o P (petite): short arm
o Q: long arm
• Autosomal Chromosomes Numbering: based the length
• Staining Chromosomes: stain to provide further identity of each
chromosome.
L. Staining Chromosomes
• Regions: starting from the centromere.
• Bands: within each region are numbered in order from the centromere to
the end of each arm
• Terms for Position: band, sub-bands, sub-sub-bands
o The numbering always goes from the centromere to the end of p or
q arms.
, 3
M. Chromosomal Location of a Gene
• Ex) CFTR
o Chromosome 7 & Long Arm Q Region #3
o Chromosomal Location: 7 q 31.2
• When solving these problems… 1st. draw the centromere, add the p and q arms.
Label regions 1, 2, 3 of your choice, within whichever region you decide which is
band 1, 2, 3.
N. Chromosome Abnormalities (Number Or Structure)
• Number Alterations:
o Aneuploidy: the change of total chromosome number, having an extra or
missing chromosomes (gain or loss).
• Structure Alterations:
o Terminal deletion, interstitial deletion, insertion, inversion, reciprocal
translocation
• Ex) Chromosome 21, Trisomy—Down Syndrome, an additional chromosome.
O. Interstitial Deletion
• The X-chromosome from the p arm region 1 and band 1 and sub-sub-band until
region 2 band 2 and sub-band 1.
o Normal chromosome is broken in two places producing 3 fragments. The
central one is lost and the outer two pieces reattach
, 4
Lecture 2: Cell Cycle Human Disease Pedigree and Hemophilia
A. Cell Proliferation
Via Cell Cycle
• Cell Proliferation:
increase in the number of cells as a result of cell growth and division—
Mitosis and Meiosis
• Somatic Cells: cells that do no produce gametes
o Normal human somatic cells are diploid with 23 pairs of
chromosomes (2N)
• Meiosis: special cell division of germ-line cells generates sperm/unfertilized
eggs (gametes).
o Gametes are haploid with 23 chromosomes (1N)
B. Mitosis
