Human genetics

QUESTIONS

-Why man requires a special methods for studies of inheritance?
-Characteristics the

Man is not a very favorable subject for studies of inheritance

The basic Human’s genetics methods are:

Pedigree analysis
Twins method
Cytological method
Populative – statistic

Pedigree Analysis

Used to determine individual genotypes;
Used to predict the mode of

Goals of Pedigree Analysis

1.Determine the mode of inheritance:
dominant, recessive, partial

Genealogical method or Pedigree analysis.
It has the following stages:
Gathering the information.
Construction

Autosomal – dominant inheritance
The autosomal dominant traits appear in every generation.

Autosomal Dominant traits:

Osteogenesis imperfecta
Brachydactyly (short fingers)
Achondroplasia (dwarfism in which the link

POLYDACTYLY

Achondroplasia

Autosomal recessive inheritance:

1.An affected individual has two normal parents, both of whom are

Autosomal recessive traits:

Albinism,
Phenylketonuria,
Galactosemia,
Gaucher’s disease,
Wilson’s disease (hepatolenticular degeneration),
Porphyria.

Albinism

Sex linked inheritance
X – linked dominant inheritance:

The X – linked dominant conditions are very rare and affected

The examples of these traits:
Vitamin D resistant rickets
Brown – coloured

X – linked recessive inheritance

X – linked recessive trait is most commonly seen in males.
The

The common examples of these traits are:
Haemophilia;
Colour blindness;
Duchane muscular dystrophy.

Twin’s method allows to determine:

role of heredity and environment in the

Coefficient of heredity (H)

Kmt – for monozygotic twins
Kdt – for