Term
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Definition
| visualization of chromosomes during metaphase |
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Term
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Definition
| at this phase the cell increases in size, protein synthesis is active, and the cell undergoes differentiation to perform its function |
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Term
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Definition
| DNA replication occurs, the chromosome number goes from 2n to 4n |
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Term
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Definition
| cell increases in size and DNA is checked for errors and are repaired. |
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Term
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Definition
| homologous chromosomes undergo exchange of short fragments of their genetic material during meiosis 1 to produce genetically different gametes |
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Term
| Features of Autosomal Dominant Pedigrees |
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Definition
-The affected children have an affected parent -Skipping of generations not common -males and females affected with equal frequency -Male to male transmission seen
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Term
| Autosomal Dominant Disorders |
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Definition
-Familial hypercholesterolemia -Huntington Disease -Myotonic Dystrophy -Marfan Syndrome -Osteogenesis Imperfecta -Achondroplasia -Acute Intermittent Porphyria -Neurofibromatosis Type I
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Term
Symptoms of Marfan Syndrome (mutation in the fibrillin gene) |
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Definition
Autosomal Dominant Disorder -Skeletal abnormalities -Hypermobile joints -ocular abnormalities (myopia, lens dislocation) -cardiovascular diseases (aneurysms) -Chest wall protruted outward |
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Term
Symptoms of Osteogenesis Imperfecta (mutation in the collagen gene) |
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Definition
Autosomal Dominant Disorder -Fragile bones that break easily -Blue sclera |
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Term
| Features of Autosomal Recessive Pedigrees |
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Definition
-Skipping of generations is common
-Males and Females are affected equally -Diseases are expressed in the homozygous state. Parents are usually carriers of the disease.
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Term
| Autosomal Recessive Disorders |
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Definition
-Most enzyme disorders -Cystic Fibrosis -Sickle cell anemia, thallasemia -Phenylketonuria -Tay-Sach's Disease |
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Term
| Features of X-Linked Recessive Pedigrees |
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Definition
-Preponderance of males
-Skipping of generations common -No male to male transmission -Fathers pass the mutation to all his daughters who are not affected. the daughters now become carriers
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Term
| X-Linked Recessive Disorders |
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Definition
-Duchene Muscular Dystrophy -Glucose 6-Phosphate Dehydrogenase Deficiency -Hemophelia A and B -Lesch-Nyhan syndrome
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Term
Symptoms of Duchene Muscular Dystrophy (mutation in the dystrophin gene) |
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Definition
X-linked Recessive Disease -Sway back -Poor muscular development -Thick lower leg muscles due to fat not muscle -belly sticks out due to weak abdominal muscles |
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Term
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Definition
X-Linked Recessive Disease -Deficiency in the clotting factor VIII leading to increased tendancy to bleed upon minor trauma -Haemarthrosis common -Subcutaneous hematomas common |
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Term
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Definition
| A phenomenon in females which the number of cells that contain an active mutant X gene are large compared to the cells that contain the active normal X |
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Term
| Features of X-Linked Dominant Pedigrees |
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Definition
-Skipping of generations not common -Preponderance of females compared to males -No male to male transmission -Affected male transmits disease to all of his daughters but none of the sons.
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Term
| X-Linked Dominant Disorders |
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Definition
-Vitamin D resistant Rickets -Incontinentia Pigmenti
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Term
| Symptoms of Incontinentia Pigmenti |
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Definition
X-Linked Dominant Disorder -Males die in utero whereas females are less severely affected -Rashes and Blisters early in life -Patches of hyperpigmentation of skin giving a 'Marble Cake Appearance' -Retinal Detachment and Mental Retardation in some patients |
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Term
| Features of Mitochondrial Inheritance Pedigrees |
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Definition
-All offsprings of affected mothers are affected -only females transmit the disease -affected males do not transmit the disease -both males and females are affected
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Term
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Definition
| variable expression in mitochondrial genes |
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Term
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Definition
Leber Hereditary optic neuropathy (progressive blindness around 20-30 years) MELAS Myoclonic epilepsy w/ ragged red muscle fibers |
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Term
| Symptoms of Fragile X Syndrome |
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Definition
X-linked Recessive Disease -A triplet repeat expansion disorder -Mental Retardation, prominent ears, elongated face, englarged testis -less severe in females -shows anticipation |
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Term
Symptoms of Prader-Willi Syndrome (paternal deletion on chromosome 15) |
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Definition
Imprinting Disease -Usually obese, mental and developmental delay, underdeveloped genitalia |
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Term
Symptoms of Angelman Syndrome (maternal deletion on chromosome 15) |
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Definition
Imprinting Disease -happy disposition, laugh inappropriately -puppet like posture of limbs |
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Term
Symptoms of Down Syndrome (Trisomy 21) |
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Definition
Increased maternal age increases risk of meiotic nondisjuntion -Mental Retardation -Short Stature -Depressed nasal bridge -Upslanting palpebral fissures -epicanthal fold -congenital heart defects -Single palmar crease |
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Term
Symptoms of Edward Syndrome (Trisomy 18) |
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Definition
-Clenched fist, overlapping of fingers -rocker bottom feet -congenital heart defects -low-set ears, small lower jaw (micrognathia) -mental retardation |
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Term
Symptoms of Patau Syndrome (Trisomy 13) |
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Definition
-Polydactyly -Cleft lip and palate -micropthalmia -microcephaly -mental retardation -cardiac anomalies |
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Term
| Symptoms of Turner Syndrome |
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Definition
X Chromosome Monosomy -Short Stature -Webbed neck -Primary amenorrhea -gonadal dysgenesis -only affects females -There is no barr body |
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Term
Symptoms of Klinefelter Syndrome (47XXY) |
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Definition
-Testicular atrophy -Gynecomastia -Female distribution of hair -Infertility |
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Term
Symptoms of Cri-du-chat Syndrome (deletion on chromosome 5) |
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Definition
-High pitched, cat like cry -mental retardation, speech problems -microcephaly |
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Term
Symptoms of DiGeorge Syndrome (deletion on chromosome 22q) |
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Definition
-Congenital heart defects -Absence of thymus -Cleft lip and palate -learning disability |
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Term
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Definition
| mutation in which a purine/pyrimidine is replace by another purine/pyrimidine |
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Term
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Definition
| A mutation in which a purine is replace by a pyrmidine and vice versa. |
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Term
| Symptoms of Xeroderma Pigmentosum |
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Definition
A defect in the nucleotide excision repair system -increased susceptibility to sunburn, blistering, freckels, upon exposure to sunlight. -high incidence of skin cancer |
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Term
| Symptoms of Bloom Syndrome |
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Definition
mutation in DNA helicase -increased risk of facial rash on exposure to sunlight and very high risk of skin cancer |
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Term
| Symptoms of Ataxia Telangiectasia |
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Definition
Mutation in a protein that stops cell division and allows for DNA repair before cell division -increased blood flow to eyes |
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Term
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Definition
| MLH1 and MSH2 mutations. these protein products help to repair mismatches made during DNA replication. |
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Term
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Definition
| BRCA1 and BRCA2 mutations. these protein products repair radiation incuded breaks, a post replication repair process |
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Term
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Definition
| A change in the nucleotide sequence that does not change the amino acid produced. |
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Term
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Definition
| An amino acid codon is changed to a stop codon resulting in premature termination of the protein |
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Term
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Definition
| A mutation that shifts the reading frame resulting in a nonfunctional protein |
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Term
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Definition
| A deletion mutation that occurs in a multiple of 3 resulting in the loss of an amino acid which if critical for protein function would result in a nonfunctional protein |
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Term
| Features of alpha-Thalassemia |
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Definition
A reduction in the synthesis of the alpha chain -deletion/promoter mutations in >2 alpha globin chains results in the disease -severe anemia (reduced HbA,HbF) |
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Term
| Features of Beta-Thalassemia |
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Definition
Reduced synthesis of the beta-chain -mutation in one of the beta-globin genes resuts in a carrier -mutation in both results in the disease -can be caused by a nonsense, promoter, splice site, or extensive deletion mutations -severe anemia and an increase in HbF and HbA2 |
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