Genetic Flashcards
(27 cards)
1
Q
Autosomal Dominant Syndromes
A
- Marfan Syndrome: FBN1 gene; connective tissue disorder with tall stature, lens dislocation, aortic root dilation.
- Neurofibromatosis Type 1: NF1 gene; café-au-lait spots, neurofibromas, Lisch nodules.
- Tuberous Sclerosis: TSC1/TSC2 genes; seizures, intellectual disability, facial angiofibromas, renal angiomyolipomas.
- Achondroplasia: FGFR3 gene; disproportionate short stature, macrocephaly, rhizomelia.
- Noonan Syndrome: PTPN11 and other RAS pathway genes; short stature, congenital heart disease (pulmonary stenosis), webbed neck.
2
Q
Autosomal Recessive Syndromes
A
- Cystic Fibrosis: CFTR gene; chronic lung disease, pancreatic insufficiency, meconium ileus.
- Phenylketonuria (PKU): PAH gene; musty odor, fair skin, intellectual disability if untreated.
- Friedreich Ataxia: FXN gene; spinocerebellar ataxia, hypertrophic cardiomyopathy, diabetes.
- Spinal Muscular Atrophy: SMN1 gene; hypotonia, progressive weakness, tongue fasciculations.
- Fanconi Anemia: Multiple FA genes; aplastic anemia, thumb/radial defects, increased cancer risk.
3
Q
X-Linked Recessive Syndromes
A
- Duchenne Muscular Dystrophy: DMD gene; early childhood onset, Gower sign, cardiomyopathy.
- Hemophilia A/B: F8/F9 genes; prolonged bleeding, hemarthrosis, X-linked inheritance.
- Hunter Syndrome (MPS II): IDS gene; coarse facial features, hepatosplenomegaly, no corneal clouding.
- Chronic Granulomatous Disease: CYBB gene; recurrent bacterial/fungal infections, catalase-positive organisms.
4
Q
X-Linked Dominant Syndromes
A
- Rett Syndrome: MECP2 gene; regression in development, hand-wringing, mainly affects girls.
- Incontinentia Pigmenti: IKBKG gene; blistering rash in infancy, swirling hyperpigmentation, dental anomalies.
- Alport Syndrome (X-linked form): COL4A5 gene; hematuria, sensorineural hearing loss, anterior lenticonus.
5
Q
Chromosomal Microdeletion Syndromes
A
- DiGeorge Syndrome (22q11.2): CATCH-22 (Cardiac defects, Abnormal facies, Thymic hypoplasia, Cleft palate, Hypocalcemia).
- Williams Syndrome (7q11.23): Elfin facies, supravalvular aortic stenosis, friendly personality.
- Cri-du-chat Syndrome (5p deletion): Cat-like cry, microcephaly, intellectual disability.
- Smith-Magenis Syndrome (17p11.2): Sleep disturbances, self-injury, intellectual disability.
6
Q
Trisomies
A
- Trisomy 21 (Down Syndrome): Hypotonia, epicanthal folds, single palmar crease, AV canal defects, increased risk of leukemia.
- Trisomy 18 (Edwards Syndrome): Rocker-bottom feet, clenched fists, prominent occiput, severe ID, CHD.
- Trisomy 13 (Patau Syndrome): Holoprosencephaly, cleft lip/palate, polydactyly, microphthalmia, severe ID.
7
Q
Single Gene Disorders
A
- Marfan Syndrome: Tall stature, aortic aneurysm, ectopia lentis.
- Achondroplasia: Rhizomelic limb shortening, normal intelligence.
- NF1: >6 café-au-lait macules, axillary freckling, optic gliomas.
- Alkaptonuria: Dark urine on standing, ochronosis, early-onset arthritis.
- Tay-Sachs Disease: Cherry-red spot, hypotonia, neurodegeneration (HEXA gene).
8
Q
Short Stature + Dysmorphism
A
- Noonan Syndrome: Webbed neck, wide-spaced eyes, PS.
- Turner Syndrome (45,X): Short stature, shield chest, streak ovaries, coarctation.
- Russell-Silver Syndrome: Intrauterine growth restriction, body asymmetry, triangular face.
- Prader-Willi Syndrome: Hypotonia in infancy, hyperphagia, obesity, short stature.
9
Q
Hypotonia + Developmental Delay
A
- Angelman Syndrome: Happy demeanor, ataxia, seizures, absent speech.
- Prader-Willi Syndrome: Hypotonia in infancy, obesity, intellectual disability.
- Rett Syndrome: Regression, hand-wringing, microcephaly in girls.
- Down Syndrome: Hypotonia, delayed milestones, moderate intellectual disability.
10
Q
Café-au-lait Spots
A
- NF1: >6 spots >5 mm in prepubertal child, >15 mm in postpubertal, neurofibromas.
- McCune-Albright Syndrome: Precocious puberty, fibrous dysplasia, endocrine issues.
- Legius Syndrome: Similar to NF1 but without tumors, SPRED1 mutation.
11
Q
Skin Lesions
A
- Incontinentia Pigmenti: Skin blistering -> wart-like rash -> swirls of hyperpigmentation.
- Tuberous Sclerosis: Ash leaf spots, shagreen patch, facial angiofibromas.
- NF1: Cutaneous neurofibromas, axillary freckling, café-au-lait macules.
12
Q
Seizures as Major Feature
A
- Tuberous Sclerosis: Infantile spasms, cortical tubers.
- Dravet Syndrome: Prolonged febrile seizures in infancy, SCN1A gene.
- Angelman Syndrome: Frequent seizures, characteristic EEG.
- Lissencephaly: Smooth brain, refractory seizures, developmental delay.
13
Q
Intellectual Disability with Dysmorphism
A
- Fragile X Syndrome: Long face, large ears, macroorchidism, CGG repeat in FMR1.
- Williams Syndrome: Full lips, stellate iris, friendly behavior.
- Down Syndrome: Almond-shaped eyes, small ears, hypotonia.
- Smith-Magenis Syndrome: Distinctive face, self-hugging, sleep problems.
14
Q
Neurogenetic Syndromes
A
- Rett Syndrome: Regression of milestones, hand-wringing, MECP2 mutation, X-linked dominant.
- Angelman Syndrome: Happy demeanor, ataxia, seizures, UBE3A deletion (maternal 15q11-q13).
- Fragile X Syndrome: Most common inherited cause of intellectual disability, CGG repeat in FMR1, X-linked.
- Tuberous Sclerosis: Cortical tubers, seizures, intellectual disability, TSC1/TSC2 genes.
- Lissencephaly: Smooth brain surface, severe developmental delay, PAFAH1B1 mutation.
15
Q
Genetic Syndromes with Congenital Heart Defects
A
- Down Syndrome (Trisomy 21): AV canal defect, ASD, VSD.
- Turner Syndrome (45,X): Bicuspid aortic valve, coarctation of the aorta.
- DiGeorge Syndrome (22q11.2 deletion): Truncus arteriosus, interrupted aortic arch, tetralogy of Fallot.
- Williams Syndrome (7q11.23 deletion): Supravalvular aortic stenosis.
- Noonan Syndrome: Pulmonary valve stenosis, hypertrophic cardiomyopathy.
16
Q
Genetic Syndromes with Endocrine Features
A
- McCune-Albright Syndrome: Precocious puberty, fibrous dysplasia, café-au-lait spots, GNAS mutation.
- Turner Syndrome: Gonadal dysgenesis, primary amenorrhea, short stature.
- Prader-Willi Syndrome: Hypogonadism, obesity, hyperphagia.
- Klinefelter Syndrome (47,XXY): Hypogonadism, tall stature, gynecomastia, learning difficulties.
- Congenital Adrenal Hyperplasia (21-OH deficiency): Virilization, salt-wasting crisis in females.
17
Q
Genetic Syndromes with Skeletal Anomalies
A
- Achondroplasia: Short stature, rhizomelia, macrocephaly, FGFR3 mutation.
- Osteogenesis Imperfecta: Bone fragility, blue sclerae, COL1A1/COL1A2 mutations.
- Thanatophoric Dysplasia: Lethal skeletal dysplasia, FGFR3 mutation.
- Ellis-van Creveld Syndrome: Short stature, polydactyly, atrial septal defects, Amish populations.
- Campomelic Dysplasia: Bowing of long bones, SOX9 mutation, often lethal.
18
Q
Genetic Syndromes with Renal Involvement
A
- Alport Syndrome: Hematuria, sensorineural deafness, COL4A5 mutation, X-linked.
- Branchio-Oto-Renal Syndrome: Ear anomalies, hearing loss, renal malformations.
- Polycystic Kidney Disease (ARPKD): Enlarged echogenic kidneys, PKHD1 mutation, pulmonary hypoplasia.
- Tuberous Sclerosis: Renal angiomyolipomas, cysts, potential renal cell carcinoma.
- BOR Syndrome: Branchial cleft cysts, hearing loss, renal anomalies (EYA1 gene).
19
Q
Genetic Syndromes with Gastrointestinal Features
A
- Hirschsprung Disease: Absence of enteric ganglia, RET gene mutations, associated with Down Syndrome.
- Peutz-Jeghers Syndrome: Hamartomatous polyps, mucocutaneous pigmentation, STK11 mutation.
- Familial Adenomatous Polyposis (FAP): APC gene mutation, hundreds of colon polyps, colorectal cancer risk.
- Juvenile Polyposis Syndrome: Multiple juvenile polyps, risk of GI cancer, SMAD4 or BMPR1A mutations.
- Alpha-1 Antitrypsin Deficiency: Hepatic dysfunction, neonatal hepatitis, liver cirrhosis, SERPINA1 gene.
20
Q
Genetic Syndromes with Immune Deficiency
A
- DiGeorge Syndrome (22q11.2 deletion): Thymic hypoplasia, T-cell deficiency, recurrent infections.
- Wiskott-Aldrich Syndrome: Thrombocytopenia, eczema, recurrent infections, WAS gene, X-linked.
- Ataxia-Telangiectasia: Cerebellar ataxia, telangiectasia, immunodeficiency, ATM gene mutation.
- SCID (Severe Combined Immunodeficiency): Absence of T and B cells, various gene mutations (e.g., IL2RG).
- Hyper IgM Syndrome: Defective CD40L, high IgM, low IgG/IgA/IgE, X-linked.
21
Q
Genetic Syndromes with Facial Dysmorphism
A
- Down Syndrome (Trisomy 21): Flat nasal bridge, epicanthal folds, upslanting palpebral fissures.
- Williams Syndrome: Elfin face, full lips, stellate iris pattern, cheerful demeanor.
- Noonan Syndrome: Hypertelorism, ptosis, low-set ears, webbed neck.
- Smith-Lemli-Opitz Syndrome: Microcephaly, ptosis, cleft palate, 2-3 toe syndactyly.
- Cornelia de Lange Syndrome: Synophrys (unibrow), long eyelashes, thin upper lip, micrognathia.
22
Q
Genetic Syndromes with Muscular Involvement
A
- Duchenne Muscular Dystrophy: Progressive muscle weakness, Gower sign, cardiomyopathy, DMD gene, X-linked.
- Becker Muscular Dystrophy: Similar to DMD but milder, later onset, DMD gene, X-linked.
- Myotonic Dystrophy Type 1: CTG repeat expansion in DMPK gene, myotonia, ptosis, cataracts.
- Pompe Disease: Glycogen storage disorder type II, floppy baby, cardiomegaly, acid alpha-glucosidase deficiency.
- Spinal Muscular Atrophy (SMA): SMN1 gene, hypotonia, tongue fasciculations, AR inheritance.
23
Q
Genetic Syndromes with Visual or Hearing Loss
A
- Alport Syndrome: Sensorineural hearing loss, hematuria, anterior lenticonus, COL4A5 mutation.
- Usher Syndrome: Congenital deafness with progressive vision loss (retinitis pigmentosa).
- Waardenburg Syndrome: Sensorineural hearing loss, white forelock, heterochromia, AD or AR.
- Stickler Syndrome: Myopia, retinal detachment, hearing loss, cleft palate, COL2A1 mutation.
- CHARGE Syndrome: Coloboma, heart defects, atresia choanae, growth retardation, ear anomalies, CHD7 mutation.
24
Q
Genodermatoses (Genetic Skin Disorders)
A
- Incontinentia Pigmenti: X-linked dominant, skin stages: vesicular → verrucous → hyperpigmented → hypopigmented.
- Epidermolysis Bullosa: Fragile skin, blistering with minor trauma, various gene defects.
- Ichthyosis Vulgaris: Dry scaly skin, filaggrin gene (FLG) mutation, AD.
- Xeroderma Pigmentosum: DNA repair defect, extreme UV sensitivity, AR.
- Tuberous Sclerosis: Hypomelanotic macules (ash leaf spots), shagreen patch, facial angiofibromas.
25
Cancer Predisposition Genetic Syndromes
- **Li-Fraumeni Syndrome**: TP53 mutation, risk of sarcoma, breast cancer, leukemia, brain tumors.
- **Beckwith-Wiedemann Syndrome**: Overgrowth, Wilms tumor, macroglossia, hemihyperplasia, 11p15 imprinting defect.
- **Familial Adenomatous Polyposis (FAP)**: APC gene, hundreds of adenomatous polyps, colorectal cancer by age 40.
- **Bloom Syndrome**: Short stature, photosensitivity, increased cancer risk, BLM gene, AR.
- **Ataxia-Telangiectasia**: Cerebellar ataxia, telangiectasias, immune deficiency, leukemia/lymphoma risk, ATM gene.
26
Genetic Syndromes with Metabolic Disorders
- **Phenylketonuria (PKU)**: PAH gene, AR, intellectual disability if untreated, musty body odor.
- **Maple Syrup Urine Disease (MSUD)**: BCKD gene complex, AR, sweet-smelling urine, encephalopathy.
- **Galactosemia**: GALT gene, AR, jaundice, hepatomegaly, E. coli sepsis in neonates.
- **MCAD Deficiency**: ACADM gene, AR, fasting hypoglycemia, lethargy, sudden death.
- **Glycogen Storage Disease Type I (Von Gierke)**: G6PC gene, AR, severe hypoglycemia, hepatomegaly.
27
Genetic Syndromes with Growth or Genital Abnormalities
- **Turner Syndrome (45,X)**: Short stature, streak gonads, primary amenorrhea, coarctation.
- **Klinefelter Syndrome (47,XXY)**: Tall stature, small testes, gynecomastia, infertility.
- **Prader-Willi Syndrome**: Hypogonadism, obesity, hyperphagia, short stature.
- **Smith-Lemli-Opitz Syndrome**: Ambiguous genitalia, growth retardation, 2-3 toe syndactyly, DHCR7 gene.
- **Congenital Adrenal Hyperplasia (21-hydroxylase deficiency)**: Female virilization, salt-wasting crisis.
