L8 Craniofacial Genetics Flashcards
Gene is a ______ unit of ________ information located on the ____________ and consisting of _________.
discrete
hereditary
chromosomes
DNA
Genome is the ________ set of ______ in the chromosomes of each cell of a human being.
complete
genes
Allele is an _______ form of a ______ that is located at a _______ position on a specific chromosome.
alternative
gene
specific
Phenotype is the _____ expression of information contained in the genetic makeup of an individual.
physical
Genotype is the _____ makeup of an organism and is inherited down to the next generation.
genetic
Homozygous means containing a pair of the _______ alleles.
same
Heterozygous means containing 2 ______ alleles
different
Chromosome is an _____ of _____ that carries _______. It has a _____ region that contains sister chromatids.
aggregate
genes
DNA
centromere
Chromosomes have ______ pairs which is responsible for various traits known as _________ chromosomes.
22
autosomal
Chromosomes have ____ chromosomes responsible for gender which is known as ______ chromosomes
2
sex-linked
Mutation is an ______ in the_______ sequence of a DNA that results in changes to a ______.
alteration
nucleotide
genome
3 types of mutations are
Harmful -organisms less able to survive (genetic disorders, cancer)
Beneficial - allow organism to better survive ( sickle cell anaemia )
Neutral - neither harmful nor helpful to organism. ( red hair )
Down syndrome occurs when an individual has a ____ or _____ extra copy of chromosome _____. Possesses _____ chromosomes and chromosome 21 undergoes _______. It is also known as _________.
full
partial
47
triplication
Trisomy 21 syndrome
_____ is the only factor that has been linked to Down Syndrome.
Maternal age
4 types of inheritance patterns are?
Autosomal Dominant Gene
Autosomal Recessive Gene
Sex-linked
Codominant
Autosomal Dominant Gene is when?
1 mutated copy of a gene in each cell is sufficent for a person to be affected by an autosomal disorder.
Autosomal Recessive Gene is when?
Both copies of genes in each cell have mutation and usually passed on by 2 carriers.
Autosomal Dominant Gene can have a _____ chance of affecting males and females. Eg is ______.
50%
Marfan syndrome
Autosomal Recessive Gene can have a _____ chance of affecting, _____ chance of carrier and _____ chance of unaffected. Eg is _____.
25%
50%
25%
Sickle cell anaemia
X-linked dominant gene is caused by _____ in genes on the ____ chromosome, one of the two sex chromosomes in each cell.
mutations
X
In X-linked dominant gene, all ______ of affected father will be affected. No ____ will be affected. _________ of affected mother have ____ chance of being affected. Eg is _____.
daughters
sons
sons and daughters
50%
Rett syndrome
X-linked recessive gene is caused by _____ in genes on the _____ chromosome. Eg is ____.
mutations
X
Haemophilia
Y-linked gene is caused by ______ in gene on the __ chromosomes. Only ____ are affected. Eg is ________.
mutations
Y
males
Y chromosome infertility
Codominance gene is when both ____ are equally strong and _____ in the hybrid genotype. Both alleles influence ____ traits. Eg is ______.
alleles
visible
genetic
ABO blood groups
Congenital abnormalities are caused by problems during the _____’s development before ______.
fetus
birth
5 categories of congenital abnormalities are?
1- chromosome abnormalities
2-single gene abnormalities
3-conditions during pregnancy that affect the baby
4-combination of genetic & environmental problems
5-unknown causes
Defects involving craniofacial dvelopment are?
Treacher Collins Syndrome
Crouzon Syndrome
Cleft palate and cleft lip
Treacher Collins Syndrome affects the development of _____ and other ______ of the face. Also known as ___________. Gene associated with _____.
bones
tissues
Mandibulofacial Dystosis
autosomal dominant gene
Symptoms of Treacher Collins Syndrome are?
-underdeveloped facial bones
-very small jaw and chin
- a cleft palate
Diagnosis of Treacher Collins Syndrome are?
-small mandible
-zygomatic bone hypoplasia
-ears are not fully formed
Prognosis of Treacher Collins Syndrome are?
-Hearing defects
-Cleft palate
-Defective tooth development
The responsible chromosome for Treacher Collins Syndrome is chromosome ____.
5
Crouzon Syndrome is a genetic disorder characterized by the ______ of certain _______.
premature fusion
skull bones
Symptoms of Crouzon Syndrome are?
-bulging eyes and vision
-beaked nose, underdeveloped upper jaw
-hearing loss
Mutations in the _____ (FGFR2) gene located on chromosome ____ causes Crouzon Syndrome. It is a _______ pattern.
fibroblast growth factor receptor 2
10
autosomal dominant
Cleft lip and cleft palate are ____ and ____ malformations that occur early in pregnancy.
facial
oral
Clefting results when there is _____ enough tissue in the mouth or lip area, and the tissue available ______ together properly.
not
do not join
What problems are associated with cleft lip and cleft palate?
-eating problems
-ear infection
-speech problems
-dental problems
A defect in the alveolus can?
-displace or rotate permanent teeth
-prevent permanent teeth from appearing
-prevent the alveolar ridge from forming
