Test 1 Flashcards
(51 cards)
Disease =
An impairment of normal physiological function of a part, organ, or system of an organism resulting from various causes (such as infection, inflammation, environmental factors, or genetic defect) and characterized by an identifiable group of signs or symptoms.
Aetiology =
the underlying cause of a disease
Carrier =
an individual who harbours the disease-causing entity but has no symptoms of disease
Epidemiology =
The study of how often diseases occur in different groups of people
Genotype =
The precise gene sequence in the DNA of an organism.
Incidence =
The rate at which a particular event or disease arises in a population (# incidents/time)
Idiopathic =
Disease of unknown aetiology
Morbidity =
State of ill-health produced by a disease
Mortality rate =
The per capita death rate caused by a disease in a population
Pathogen =
A disease causing organism such as bacteria or virus
Pathogenesis =
The manor by which a disease develops
Phenotype =
Observable characteristics of an organism (typically linked with other information regarding that organism, e.g. genetics, environmental conditions).
Prevalence =
The proportion of the population affected by a disease at a particular time.
Prognosis =
Probable outcome of a disease (e.g. in terms of severity/timing).
Symptom =
Subjective manifestation, such as weakness or pain, in an affected individual. (Objective manifestations detectable by a clinician are usually referred to as signs or physical findings)
Diseases are caused by…
a combination of both genetic and environmental factors
Hereditary =
derived from one´s parent
Familial =
transmitted through generations and affecting several members of a family
Congenital =
present at birth
not all genetic disorders are congenital (Huntington disease: 3rd-4th decade)
not all congenital diseases are of genetic origin (congenital syphylis, toxoplasmosis)
Autosomal dominant:
One mutated copy of the gene in each cell is sufficient for a person to be affected
Typically - an affected person inherits the condition from an affected parent
Occasionally - the condition may result from a new mutation in the gene and occur in people with no history of the disorder in their family
Examples: Huntington’s disease, Marfan syndrome
Autosomal recessive:
Both copies of the gene have mutations in affected individuals.
The parents of an individual with an autosomal recessive condition each carry (at least) one copy of the mutated gene, but they (typically) do not show signs and symptoms of the condition.
Examples: Cystic Fibrosis, sickle cell disease
X-Linked dominant:
A mutation in one copy of the gene in each cell is sufficient for a person to be affected.
Both genders are affected, but males are typically more severely affected in females, due to X chromosome inactivation (lyonisation). Fathers do not pass on the affected allele to sons (no male-to-male transmission).
Example: Fragile X syndrome
X-linked recessive:
All copies of the gene have mutations in affected individuals (one in males, two in females).
These diseases occur predominantly in males because it is less likely that a female will inherit two copies (or that selective X-inactivation would occur favouring the non-mutated allele). Fathers do not pass on the affected allele to sons (no male-to-male transmission).
Examples: Hemophilias, Fabry disease
Y-linked:
Caused by of the gene mutations on the Y chromosome. Occurs only in males.
Example: Y-chromosome infertility
