Lecture 1 Flashcards
Human Genetics
the science of heredity and variation in humans.
Medical Genetics
the subset of human genetics that is important in medicine and medical research
Molecular Genetics
the study of the structure and function of individual genes
Clinical Genetics
the application of genetics to diagnose and patient care. applied to individuals and families.
how do genetics disorders arise?
when a gene does not perform its normal function
what is the study of genes and their function about?
the relationship between genotype and phenotype
what is 100K?
government lead programme aiming to map 100,000 NHS patient gene.
what are the types of genetic disorders?
- single gene
- chromosomal
- mitochondrial
- imprinted
what are genetic biomarkers?
tests (e.g. blood test) to determine the risk of being predisposed to a genetic disorder. this can be used in cancer profiling
what is pharmacogenetics?
variations in drug response is linked to genetic variation. pharmacogenetics can determine whether a drug will be beneficial to a person based on their genetics.
Give example of a drug which works best for patients with a particular expression of genes.
IMATINIB (GLEEVEC) - drug for leukaemia -works on best on a specific mutation FACTOR IX -replacement clotting factor for Haemphilia B -a specific gene intervention
Reason to refer a child to clinical genetics
- birth anomalies
- malformation
- Dysmorphic features
- learning difficulties
Reasons to refer an adult to clinical genetics
- diagnosis
- predictive testing
- carrier testing
- family history (cancer)
reasons to refer a pregnant lady to clinical genetics
- known genetic disorder in family
- abnormality detected in screening
- fetal loss or recurrent miscarriage
what is the role of a family tree in genetic diagnosis?
detect a pattern of inheritance
what is the role of physical examinations in genetic diagnosis?
to direct testing and inform precise diagnosis
what do genetic tests involve?
chromosome - karyotype
Genes- DNA testing
what are the non-genetic tests used in diagnosing genetic disorders?
- blood test
- X rays
what is enzyme assays (non-genetic test) used to diagnose?
Inborn errors of metabolism
what is Haematology (non-genetic test) used to diagnose?
Thalassaemia
what is X-rays used to diagnose?
skeletal dysplasia (achondroplasia)
what types of genetic tests are used to diagnose disorders involving genetic architecture?
- Cytogenetics
- Array based techniques
what types of genetic tests are used to diagnose disorders involving genetic faults?
- sequencing
- OLA assays
- MLPA tests
why are diagnostic testing useful?
- finds exact cause
answers both specific and broad questions
why are predictive testing useful?
Testing based on predisposition (e.g. Family). when the disorder is not clinically visible and would therefore effect individual’s life.
why are carrier testing useful?
testing for recessive disorders including autosomal and X-linked
why are prenatal testing useful?
Preventative genetic disease. tests on amniotic fluid, chorionic villus sampling
what are the advantages and disadvantage of genetic tests?
Advantage:
- early diagnosis = early intervention
- carrier testing = reproductive choices
- prenatal testing = reproductive choices
disadvantages:
- discover disorders which may be un-treatable and affect patient’s quality of life e.g. alzeimers
what is genetic counselling?
an education process that seeks to assist affected (or at risk) individuals to understand genetic disorder, how it is transmitted, and treatment and management options (prognosis ) and family planning
pharmacogenomics
analysis of entire genomes across groups of individuals the genetic factors influencing responses to a drug
pharmacogenetics
studying an individual’s genetic make-up to predict responses to a drug and guide prescription. Example: cancer
