Genetics Flashcards
DYSPLASIA:
congenital abnormal or defective development of tissue or organ
Recessive
Two copies of the gene is necessary for the condition
Chromosomes are made up of _______ that code for traits.
genes
Mixed up pieces
translocations
The remaining _____ include all the other forms of inheritance.
15%
30-40% of hereditary hearing loss is
syndromic
Multifactorial
Inheritance controlled by many genes with small additive effects (polygenic) plus the effects of the environment.
Gene:
a section of DNA with the coded instruction for the production of a protein that is essential for the growth
Locus
the site of the gene on a chromosome.
In a majority _______ of genetic cases, hearing loss is an isolated finding (non syndromic)
(60-70%)
All the mitochondrial DNA are in the ________ not nucleus.
cell cytoplasm
Phenotype:
- the trait produced by a single gene or several genes;
- the total of all observable features of an individual
A gene is found at a specific location or locus on a
____________.
chromosome.
About ________ the cases of congenital HL/deafness are due to non-genetic factors.
half (40-50%)
Karotype:
pattern of all chromosomes laid out, a photographic record
Mixed up pieces
translocations
Genetics:
The study of heredity and how traits are passed on through generations.
Genome/genotype:
the total genetic make-up of a specific organism.
Too few chromosomes
monsomy
Approximately _____ is inherited in a an autosomal recessive pattern
70%
The 23 pairs consist of _______ pair of sex chromosomes
one
Most human cells contain _________ each which contains a small chromosome with a small number of genes.
several hundred mitochondria
Syndrome:
a collection of associated abnormalities and symptoms.
There are _______ known genetic causes involving hearing loss.
over 400
Too few chromosomes
monosomy
____ acts like the letters, _____ are like sentences, and __________ are like chapters in a book.
- DNA
- genes
3 chromosomes
Congenital deafness/profound hearing loss occurs in approximately _________________.
1 out of every 1000 births.
About ________ of cases of congenital HL/deafness are due to genetic factors.
half (50-60%)
Pairs of autosomes are called ___________.
homologous chromosomes.
Dominant
Only one copy of the gene is necessary for the condition
Too many chromosomes:
trisomy
Penetrance:
the REGULARITY which which an inherited trait is manifested in the person who carries the gene.
The other 22 pairs are referred to as _________.
autosomes
Polygenic
Large number of genetic factors, each making only a small contribution to the final phenotype
Each person has ______ chromosomes packaged in every cell of the body
46
Approximately _____ of genetic HL is inherited in an autosomal dominant pattern.
15%
