Genetic disorders affecting communication Flashcards
Define gene
a region of DNA that codes for a specific protein
What is an exon?
a region of coding DNA
What is an intron?
a region of non-coding DNA
What is a sequence?
the order of bases in a stretch of DNA
How can variants be identified?
through genetic sequencing
Define genetic disorder
A health problem caused by one or more abnormalities to the genome
What can cause a genetic disorder?
- mutation in one gene
- mutation in multiple genes
- chromosomal abnormality
What is a rare disease?
occurs in less than 1:2000
How many people in UK have a rare disease?
3.5 million
How many rare conditions have been identified?
more than 7000
How many rare diseases are caused by genetic change?
80%
Define developmental disorder
- neurologically based condition that can interfere with acquisition, retention, or application of specific skills or sets of information
- any disorder that begins at an early age and significantly affects psychological functioning
What are the types of genetic disorder?
- single gene disorder
- chromosomal disorders
- mitochondrial disorders
- complex multifactoral disorders
What is a single gene disorder?
A change in the DNA sequence of a single gene
What are chromosomal disorders?
Due to abnormal changes in parts of, or whole chromosomes
What are mitochondrial disorders?
due to errors in mitochondrial DNA
What are complex multifactoral disorders?
due to errors in several different genes
How is a single gene disorder classified?
autosomal or sex-linked
What are the features of single gene disorders?
- hereditary
- affect every cell in the body
What is the inheritance pattern for autosomal dominant disorder?
only one copy of dominant allele needed in genotype for disease to be expressed in phenotype
What is the inheritance pattern for an autosomal recessive disorder?
two copies of a recessive allele are needed in genotype for disease to be expressed in phenotype
What is a sex linked inherited disorder caused by?
a mutation on the X chromosome
What are the different types of chromosomal disorder?
- chromosomal duplication
- aneuploidy
- chromosomal fusion
What is aneuploidy?
the gain or loss of one chromosome
What is trisomy?
the gain of one chromosome
What is monosomy?
the loss of a chromosome
Define syndrome
A disease or disorder that has numerous symptoms and identifying features