Download 3. human genetic disorders.

6. HUMAN GENETICS.
What are the causes of variation in humans?
How is karyotype studied?
How are genetic diseases diagnosed?
What information can a family tree give us??
1. INHERITANCE AND HUMAN VARIATION.
People have many characteristics that distinguish them from each
other. There are two main causes of this variety.
•GENETIC DIFFERENCES. Genetic traits are inherited and make up the
GENOTYPE of an individual.
1. INHERITANCE AND HUMAN VARIATION.
•ENVIRONMENTAL FACTORS. These are factors such as food and
lifestyle habits. These effects that they produce in the phenotype are
“not” transmissible to offspring.
1. INHERITANCE AND HUMAN VARIATION.
1.2 QUALITATIVE TRAITS.
HAVE ONLY A SMALL NUMBER OF ALTERNATIVE EXPRESSIONS.
ABILITY TO ROLL THE TONGUE IN A U-SHAPE, STRAIGHT HAIR AND
CURLY HAIR…
ARE USUALLY DETERMINED BY A PAIR OF ALLELES THAT ARE LOCATED
ON A SINGLE LOCUS.
BLOOD GROUPS.
ABO SYSTEM.
BLOOD GROUPS.
ABO SYSTEM.
BLOOD GROUPS.
ABO SYSTEM.
BLOOD GROUPS.
RH.
2. GENETICS STUDIES IN HUMANS.
2.1 HUMAN KARYOTYPE STUDIES.
A karyotype is a profile of the number, type and structure of
chromosomes found in the cell of a particular species. If the karyotype
of a species is known, the chromosomes of individuals can be
compared to the species´ standard chromosome pattern. This help to
detect anomalies.
2. GENETICS STUDIES IN HUMANS.
What happens when a person has
something different, such as too
many or too few chromosomes,
missing pieces of chromosomes, or
mixed up pieces of chromosomes?
2. GENETICS STUDIES IN HUMANS.
2.1 HUMAN KARYOTYPE STUDIES.
ANOMALIES.
2. GENETICS STUDIES IN HUMANS.
2.1 HUMAN KARYOTYPE STUDIES.
ANOMALIES.
2. GENETICS STUDIES IN HUMANS.
2.2 DIAGNOSIS OF GENETIC DISEASES.
Amniocentesis procedure.
For couples who have already had a child with a
chromosome anomaly.
If either one or both partners have a family history
of genetic disease.
When the pregnant woman is over 35 years old.
2.2 DIAGNOSIS OF GENETIC DISEASES. Amniocentesis procedure.
3. HUMAN GENETIC DISORDERS.
Defective genes that don´t have the correct amount or type of
information can cause anomalies in how the body functions and
often lead to the appearance of serious diseases.
•CANCER.
3. HUMAN GENETIC DISORDERS.
•CANCER.
3. HUMAN GENETIC DISORDERS.
•CANCER.
3. HUMAN GENETIC DISORDERS.
•CANCER.
3. HUMAN GENETIC DISORDERS.
3.1 AUTOSOMAL DISORDERS.
The genes involved in these types of disorders are found in one of the
22 pairs of autosomes. The transmission of theses defective genes can
therefore affect women and men equally.
AUTOSOMAL DOMINANT DISORDERS. (Polydactyly)
3. HUMAN GENETIC DISORDERS.
3.1 AUTOSOMAL DISORDERS.
AUTOSOMAL RECESSIVE DISORDERS. (Albinism)
3. HUMAN GENETIC DISORDERS.
3.2 SEX-LINKED DISORDERS.
3. HUMAN GENETIC DISORDERS.
3.3 INHERITANCE INFLUENCIED BY SEX.
In some cases, an autosome trait has a different dominance depending
on the sex of the individual. This means that men and women can show
different phenotypes with the same genotype.
Some types of baldness can be determined by an autosome allele. It is
recessive in females and dominant in males.
4. DISORDERS RELATED TO CHROMOSOME NUMBER.
Any change in the number of chromosomes in the
human genome results in the appearance of
genetic condition. These diseases vary from
moderate to very serious.
4.1 AUTOSOMAL DISORDERS.
These types of genetic disorders are the results of changes in the
number of autosomes:
Down syndrome.
4.1 AUTOSOMAL DISORDERS.
Down syndrome.
4.1 AUTOSOMAL DISORDERS.
Down syndrome.
4.1 AUTOSOMAL DISORDERS.
Patau syndrome.
4.1 AUTOSOMAL DISORDERS.
Patau syndrome.
4.2 SEX CHROMOSOME DISORDERS.
These diseases can be caused by the addition or loss of sex
chromosomes. The symptoms of sex chromosome disorders are
generally less serious than those of autosomal diseases such as
trisomy disorders.
Triple X Syndrome.
4.2 SEX CHROMOSOME DISORDERS.
Triple X Syndrome.
4.2 SEX CHROMOSOME DISORDERS.
XYY Syndrome.
4.2 SEX CHROMOSOME DISORDERS.
XYY Syndrome.
5. CHANGES IN CHROMOSOME STRUCTURE.
Some diseases are caused by changes in
chromosome structure.
5. CHANGES IN CHROMOSOME STRUCTURE.
These alterations can be detected by studying the affected
person´s karyotype:
DELETION: A piece of chromosome is missing. This often
causes anomalies in the skeleton and intellectual disabilities.
5. CHANGES IN CHROMOSOME STRUCTURE.
5. CHANGES IN CHROMOSOME STRUCTURE.
DUPLICATION: There are cases when part of a chromosome is
repeated.
5. CHANGES IN CHROMOSOME STRUCTURE.
Diseases related to chromosome 2p duplication.
5. CHANGES IN CHROMOSOME STRUCTURE.
INVERSION. A piece of chromosome is reversed.
5. CHANGES IN CHROMOSOME STRUCTURE.
Pericentric Inversion of Chromosome 9 (inv[9][p11q13])
5. CHANGES IN CHROMOSOME STRUCTURE.
TRANSLOCATION. A piece of chromosome becomes attached
to a different chromosome.
5. CHANGES IN CHROMOSOME STRUCTURE.
Overview of some chromosomal translocations involved in
different cancers, as well as implicated in some other conditions,
e.g. schizophrenia
DEVELOPMENT OF BASIC COMPETENCES
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