Genetic Syndromes Flashcards
What is the inheritance of congenital adrenal hyperplasia?
Autosomal recessive
How is Prader-Willi Syndrome inherited?
Usually sporadic deletion on the paternal 15q (95% cases sporadic, 5% AD)
How is Shwachman-Diamond syndrome inherited?
Autosomal recessive
Pancytopaenia with exocrine pancreas dysfunction suggests…
Shwachman-Diamond Syndrome
What is the genetic test of choice for DiGeorge Syndrome?
FISH
Achondroplasia is caused by mutations in which gene?
FGFR3
Tuberous sclerosis is caused by mutations in which gene?
TSC1
What proportion of children with Trisomy 21 have cardiac defects?
1 in 3
Patau Syndrome is Trisomy…
13
Edwards’ Syndrome is Trisomy…
18
Small head, low-set ears and ‘rocker bottom feet’ suggests…
Edwards’ Syndrome
What karyotype is present in Klinefelter’s Syndrome?
47XXY
A male with gynaecomastia, sparse pubic hair, small testes and infertility suggests…
Klinefelter’s Syndrome
What is the mechanism of Klinefelter’s?
Paternal non-disjunction during meiosis
Short stature, webbed neck and high palate suggests…
Turner’s Syndrome
What is the karyotype for Turner’s Syndrome?
45XO / 45X
How is Noonan’s Syndrome inherited?
AD
Short stature, wide space between eyes and low-set ears suggests…
Noonan’s Syndrome
What is the main complication associated with Noonan’s Syndrome?
Congenital heart disease
What are the main congenital heart defects associated with Noonan Syndrome?
Pulmonary stenosis, HOCM, ASD
Which cardiac problems are associated with Marfan’s Syndrome?
Aortic/mitral valve prolapse and aortic aneurysm
What is the genetic basis for Fragile X Syndrome?
Mutation in FMR1 gene on X Chromosome
Male with ID, long & narrow face suggests…
Fragile X Syndrome
Which medical treatment may be indicated in Prader-Willi Syndrome?
Growth hormone
What is the genetic basis of Angelman Syndrome?
Loss of function of maternal UBE3A gene due to a microdeletion on chromosome 15
Child with ID, happy demeanour and widely-spaced teeth suggests…
Angelman Syndrome
Friendly, broad forehead and ‘starburst eyes’ suggests…
William Syndrome
What is the genetic basis for William Syndrome?
Deletion of genetic material on chromosome 7
Which cardiac defect is associated with William Syndrome?
Supravalvular aortic stenosis
How is hereditary spherocytosis inherited?
Autosomal Dominant
What is the quickest genetic test for Down Syndrome?
QF-PCR for chromosome 21
Insensitivity to pain suggests which genetic syndrome?
Lesch-Nyan Syndrome
What is the inheritance pattern of Chediak-Higashi syndrome?
AR
Asymmetric limb growth and hypoglycaemia suggests…
Beckwith-Weideman Syndrome
Which malignancy is associated with Beckwith-Weideman Syndrome?
Neuroblastoma
How is SMA inherited?
AR
What is the genetic basis of SMA?
Deletion of SMN gee on chromosome 5q
What is the genetic basis for congenital myotonic dystrophy?
CTG repeat on chromosome 9
Rett Syndrome almost exclusively affects…
Females
What is the genetic basis for Rett Syndrome?
Sporadic mutations in MECP2 gene on X chromosome
Child with developmental regression, acquired microcephaly and stereotypic movements suggests…
Rett Syndrome
What is the prognosis for Rett Syndrome?
Most live til 40-50s, most wheelchair bound by age 10
Inherited progressive ataxia, weakness and sensory deficits suggests…
Friederich’s ataxia
What is the inheritance pattern of Friederich’s ataxia?
AR
What is the genetic defect in Friederich’s ataxia?
GAA trinucleotide repeat in FXN gene on chromosome 9
What is the most common cause of death in Friederich’s ataxia?
HCM
Overgrowth since birth, developmental issues, long, narrow face with pointed chin suggests…
Sotos syndrome
Which tumours are associated with MEN1?
3Ps - pituitary, parathyroid, pancreatic
Which gene is affected in MEN1?
MEN1
Which gene is affected in MEN2?
RET
Which tumours are associated with MEN2A?
1M, 2Ps - MTC, parathyroid, phaeo
Which tumours are associated with MEN2B?
2Ms, 1P - MTC, marfinoid/neuroma, phaeo
Which tumours are associated with VHL?
retinal/cerebellar haemangiomas
Renal and extra-renal cysts
What is the genetic basis of McCune-Albright Syndrome?
Sporadic mutation in GNAS
Cafe-au-lait spots, precocious puberty and joint pain suggests…
McCune-Albright Syndrome
In NF1 there is an increased risk of which tumours?
Optic gliomas and phaeo’s
In NF2 there is an increased risk of which tumours?
Nervous system - schwannomas, ependymomas, meningiomas
Which ion channel is usually affected in long QT syndrome?
K+
Which ion channel is usually affected in long QT syndrome?
K+
Which ion channel is usually affected in long QT syndrome?
K+
What is the pattern of mitochondrial inheritance?
Always inherited from mother
All children of affected mothers affected
No children of affected males affected
Inherited infantile encephalopathy and neurological symptoms suggests…
Leigh Syndrome
Inherited pigmentary retinopathy, myopathy and deafness suggests…
Kearns-Sayre Syndrome
Stroke-like episodes, seizures and lactic acidosis suggests…
MELAS
Which protein is defective in Marfan Syndrome?
Fibrillin-1
How is Bartter Syndrome inherited?
AR
What is the defect in Bartter Syndrome?
Salt-wasting due to inability to re-absorb salts in the thick ascending loop of henle - due to NKCC2 or ROMK defects
‘Almond-shaped eyes’ suggests…
Prader-Willi Syndrome
What is the chance of affected offspring if one parent has a balanced robertsonian translocation of chromosome 21?
100%
Broad nose, neonatal hypercalcaemia and aortic stenosis suggests…
Williams Syndrome
What is the genetic basis of Williams syndrome?
Microdeletion chromosome 7
What is the first-line genetic test for developmental delay?
Microarray