KARYOTYPES

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KARYOTYPES THE HUMAN GENOME
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KARYOTYPES THE HUMAN GENOME

• To analyze chromosomes, scientists photograph
  cells while they are undergoing mitosis when the
  chromosomes are fully condensed easy to see.
• They then cut out the chromosomes from the
  photographs arrange them together in homologous
  pairs.

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KARYOTYPES THE HUMAN GENOME

• A picture of chromosomes arranged in this way is
  called a karyotype, like the picture at left.

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KARYOTYPES THE HUMAN GENOME

• To review, humans have 46 chromosomes in each of
  our body cells 23 in each of our sex cells.
• Recall that the 23rd pair of chromosomes are
  called sex chromosomes they determine a
  persons gender.
• Mutations can occur on any of our 23 pairs of
  chromosomes.

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KARYOTYPES THE HUMAN GENOME

• Karyotypes play an important role in identifying
  genetic disorders, as they can give doctors a
  preview to the genome of an unborn child help
  diagnose a disorder in someone who has physical
  or mental signs that there is something wrong
  with them.

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GENETICISTS

• A geneticist is a scientist that works in the
  laboratory doing molecular research or collecting
  and analyzing family histories and counseling
  families on genetic diseases disorders.
• They have the opportunity to discover new genes
  can possibly help cure genetic disorders.

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SEX-LINKED TRAITS

• There is a special pattern of inheritance for
  genes located on the X and Y chromosomes.
• Because their chromosomes determine ones gender,
  genes located on these chromosomes are called
  sex-linked genes.

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SEX-LINKED TRAITS
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SEX-LINKED TRAITS

• More than 100 sex-linked genetic disorders have
  now been mapped to the X chromosome.
• The Y chromosome is much smaller than the X
  chromosome appears to contain only a few genes.

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SEX-LINKED TRAITS

• Males have only one X chromosome, therefore all
  X-linked alleles are expressed in males, even if
  they are recessive traits.
• Colorblindness, hemophilia and muscular dystrophy
  are considered sex-linked traits.

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DNA ANALYSIS

• Due to the great diversity of the human genome
  (all of the genes in a humans body), we can be
  sure that no two individuals are exactly the same
  (except identical twins).

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DNA ANALYSIS

• DNA Fingerprinting is a specific form of genetic
  testing that analyzes sections of hair, blood,
  sperm or skin tissue to locate patterns of bands
  in the DNA that distinguishes one person from any
  other person in the world.
• This often helps solve criminal cases or free
  someone who has been wrongfully accused and
  convicted of a crime.

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DNA ANALYSIS
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HUMAN GENOME PROJECT

• This project is an ongoing effort to analyze the
  human genome in order to map genes determine
  what causes certain diseases, to give us clues to
  some of the properties of life and to find
  information that may be useful in developing
  drugs treatments for disease.

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ETHICAL ISSUES

• Many ethical issues exist in the advancement of
  genetics.
• Scientists have determined that some cells (stem
  cells) can be manipulated with the hopes of one
  day curing diseases disorders, however many
  people fear that cloning, harvesting stem cells
  from fertilized cells and other such genetic
  manipulations will result in a self-engineered
  society.

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ETHICAL ISSUES