Download Genetic Disorders and Syndromes: Definitions and Characteristics and more Quizzes Human Genetics in PDF only on Docsity! TERM 1 Down's Syndrome DEFINITION 1 Mutation: trisomy 21 Caused meiotic non-disjunction (maternal in meiosis I, paternal in meiosis II) chance of occurance increases with age of parents viable trisomy mental retardation and physical abnormalities TERM 2 Cri Du Chat Syndrome DEFINITION 2 Mutation: deletion at 5p mewing like a cat, mental retardation, physical abnormalites, heart abnormalities translocation of carrier parent, thought is that haploinsuffiency causes some of these symptoms to arise 10-15% sporadic TERM 3 Beckwith-Wiedemann syndrome DEFINITION 3 Mutation: imprinting defects at 11p15 Causes abnormal expression of IGF2 (stimulate growth) and/or CKDNIC (inhibit growth), and another gene is expressed that does not code for a protein many things can cause this syndrome, though methylation seems to be most common (uniparental disomy is possible where both copies of the gene are from one parent) TERM 4 Prader-Willi syndrome DEFINITION 4 Mutation: imprinting mutation at 15p11-15p13 deletion of paternal chromosome at that site (maternal uniparental disomy) symptoms include cognitive impairment, sterility, TERM 5 Angelman syndrome DEFINITION 5 Mutation: imprinting mutation at 15p11-15p13 deletion of maternal chromosome at this site (uniparental disomy of father) TERM 6 Sex reversal DEFINITION 6 genotype female, pheno male genotype male, pheno female translocation of SRY gene to Xp of sex chromosome (for male XX) both individuals sterile because need other genes on "missing" chromosome to do full maturation of sperm and eggs TERM 7 Turner syndrome DEFINITION 7 Mutation: 45 chromosomes, X0 genotype for sex paternal non-disjunction sterility TERM 8 Kleinfelter syndrome DEFINITION 8 Mutation: XXY genotype, phenotype male paternal or maternal meiosis I more likely to survive autodominant diseases like Rett's syndrome since 1 copy of the mutation with a loss of heterozygousity will kill the child TERM 9 Cystic fibrosis DEFINITION 9 Stats: mostly white population, 1/3000, higher in isolated pops Inheritance:autosomal recessive, allelic heterogenity Symptoms:exocrinepancreatic insufficiency, progressive pulmonary disease, obstructie azospermia, elevated sweat chlorid concentration, growth failure Cause:defective cystic fibrosis transmembrane conductance regulator, functions to maintain adequate hydration of mucus secretion in lung and epithelial TERM 10 Xeroderma Pigmentosum DEFINITION 10 Stats: ~1/mill in US + Europe, 1/100000 in Japan Inheritance:autosomal recessive, locus heterozygousity, allelic heterogenity Symptoms:UV light sensitivity, skin cancer, neurological dysfunction, can causecockayne syndrome Cause:DNA repair dysfunction during transcription, TERM 21 Sickle Cell anemia DEFINITION 21 S gene, heterzygous protects against malaria NO ALLELIC HETEROGENITY forms precipitate that forms gelationous network that causes RBC to lose shape and elasticity autosomal recessive missense at HBB TERM 22 Autosomal Dominant polycystic kidney disease DEFINITION 22 stats: 1/300 -1/1000 live births strong allelic but some locus heterogenity mutations in PKD1 or PKD2 Two-hit mechanism (loss of heterozygousity) (looks like autosomal dominant) interferes with cell-to-cell interactions, increase in defective cell, cysts grow in kidney TERM 23 Hereditary hemochromatosis DEFINITION 23 too much iron build up, regular phlebotomy will help drain blood usually in european populations, does not have regulating gene that stops uptake of iron when levels are sufficient HFE gene autosomal recessive TERM 24 Fragile X syndrome DEFINITION 24 CGG repeat in ___ chromosome, make "indent" in chromosome X-linked, allelic heterogenity insertion in 5' UTR fully pentrant males and semi=pentrant females more repeats more severe the phenotype TERM 25 Charcot-Marie-Tooth disease DEFINITION 25 copy number polymorphism autosomal dominant over expression of PMP22 gene muscle degeneration TERM 26 Hemolytic Disease of the Newborn DEFINITION 26 mother Rh negative, baby Rh positive protein polymorphism for Rh positive Rh negative TERM 27 Alzheimer disease DEFINITION 27 hereditary and sporadic, AB40 and AB42 accumulations epsilon4 is most predominantly associated with disease but still false positives and negatives TERM 28 insulin-dependent diabetes mellitus DEFINITION 28 Type 1 TERM 29 non-insulin dependent diabetes mellitus DEFINITION 29 Type 2 TERM 30 Crohn Disease DEFINITION 30 ulcers throughout large intestine NOd2 TERM 31 Age-related macular degeneration DEFINITION 31 late onset retinal degeneration, inflammatory/complement response TERM 32 Thalassemia DEFINITION 32 multiple forms hereditary persistance of fetal hemoglobin TERM 33 Chronic Myelogenous Leukemia DEFINITION 33 translocation of philadelphia chromosome trigger growth cell signalling in WBC TERM 34 Retinoblastoma DEFINITION 34 autosomal dominant two hit mechanism RB1 gene, tumor suppression checkpoint checkers TERM 35 Li-Fraumeni syndrome DEFINITION 35 breast cancer??? TP53 tumor suppressor gene, p53 protein
