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Miller-Dieker Syndrome (17p13.3 Deletion Syndrome)
157 Miller-Dieker Syndrome
(17p13.3 Deletion Syndrome) KATHERINE R. GOETZINGER | ALISON G. CAHILL
Introduction Miller-Dieker syndrome (MDS) is a rare, contiguous gene deletion syndrome characterized by type I lissencephaly, facial dysmorphism, seizures, and severe mental retardation.1–3 Other associated defects including cardiac malformations, neural tube defects, omphalocele, gastrointestinal anomalies, genitourinary anomalies, and intrauterine growth restriction have also been described in relationship to this syndrome.3–6 MDS is caused by a deletion at the chromosome 17p13.3 locus and is thought to represent the severe end of the spectrum of classical lissencephaly.7,8 The prognosis for affected patients is poor, with mortality typically occurring within the first 1 to 2 years of life.3,9
Disorder DEFINITION Lissencephaly is a defect in neuronal migration characterized by a smooth cerebral surface, either with agyria (absent gyri) or pachygyria (abnormally broad brain folds), a thickened cerebral cortex, and an increased ratio of gray to white matter. Mutation in the causative LIS1 gene leads to a spectrum of disorders encompassing isolated lissencephaly, subcortical band heterotopia, and MDS.10 Patients with MDS tend to have larger deletions, resulting in more severe lissencephaly in combination with craniofacial dysmorphisms, as well as other associated anomalies.3,11,12 PREVALENCE AND EPIDEMIOLOGY Due to the rarity of disease, the prevalence of MDS is unknown. At least 29 cases of MDS with the 17p13.3 deletion and prenatal findings have been reported in the literature.13 Classical lissencephaly is reported to occur in 11.7–40 : 1 million births.14 ETIOLOGY, PATHOPHYSIOLOGY, AND EMBRYOLOGY Impaired neuronal migration between 6 and 15 weeks’ gestation is the underlying etiologic mechanism for lissencephaly. Postmitotic neurons are unable to migrate to their final destination and therefore do not correctly populate the cortical plate of the cerebral cortex. This leads to the absence of sulci and gyri on the surface of the brain, as well as abnormal cortical thickness. Heterozygous deletions in the region of chromosome 17p13.3 result in the MDS phenotype. Located within this region is the responsible lissencephaly gene (LIS1 or PAFAH1B1), which has been highly conserved throughout evolution. This gene encodes 636
the β subunit of the platelet-activating factor acetylhydrolase brain isoform, which inactivates platelet-activating factor, a neuroregulatory molecule.7,15 While deletions in LIS1 are observed in both isolated lissencephaly and MDS, it is thought that the more severe phenotype observed in MDS is caused by a combined genetic effect from deletions in both LIS1 as well as the YWHAE gene, located about 40 kb telomeric to LIS1 within a region known as the “MDS telomeric critical region.”7,10,16,17 Loss of the YWHAE gene, not including LIS1, results in facial dysmorphism, intrauterine growth restriction (IUGR), and neuroradiologic changes.18 Large deletions that extend farther toward the 17p telomere, including the YWHAE gene, result in the more severe phenotype as observed in MDS.12,17,19 Approximately 80% of patients with MDS have a de novo deletion in the 17p13.3 region, and the remaining 20% are thought to inherit the deletion from a parent who carries a balanced chromosomal translocation.20 MANIFESTATIONS OF DISEASE Clinical Presentation The clinical features of MDS include profound neurodevelopmental delay, seizure activity, failure to thrive, and feeding difficulties. Infants are typically hypotonic at birth and subsequently develop spasticity. The classic facial dysmorphisms include a prominent forehead, low-set ears, widely spaced eyes, a thickened upper lip with a thin vermillion border, an elongated philtrum, a short, upturned nose, bitemporal narrowing, and micrognathia.3,21 Other variable findings include microcephaly, clubfoot, polydactyly, cleft lip/palate, omphalocele, duodenal atresia, hepatosplenomegaly, sacral dimples, joint contractures, hypoplastic genitalia in affected males, and renal and cardiac malformations.3,6,22 Imaging Technique and Findings Ultrasound. The sonographic evaluation for lissencephaly at the time of the midtrimester anatomic survey poses a diagnostic challenge given that brain development and maturation, including formation of normal cerebral gyration, continues throughout gestation. Suspicious sonographic findings include an absent parietooccipital and calcarine fissure as well as a smooth, shallow sylvian fissure, which can be detected in the standard plane used to measure biparietal diameter (Fig. 157.1). These findings have been reported on prenatal ultrasound (US) as early as 23 weeks’ gestation. It is important to note that prior to 20 weeks’ gestation, it is normal for the sylvian fissure to appear as a smooth, shallow depression.23 Other central nervous system (CNS) findings such as ventriculomegaly and agenesis of the corpus callosum (ACC) can be markers for lissencephaly. IUGR and polyhydramnios (secondary to impaired fetal swallowing) are common
157 Miller-Dieker Syndrome (17p13.3 Deletion Syndrome)
A
637
B
Fig. 157.1 (A) Axial ultrasound image at 23 weeks’ gestation demonstrating a shallow/flat sylvian fissure (arrow) in a fetus with Miller-Dieker syndrome. (B) Normal “square” appearance of the sylvian fissure (arrows).
• Walker-Warburg syndrome (type 2) • Fukuyama congenital muscular dystrophy (type 2) • Baraitser-Winter syndrome Other syndromes associated with facial dysmorphisms, seizures, microcephaly, and hypotonia include Cornelia de Lange, WolfHirschorn, Smith-Lemli-Opitz, and Zellweger syndrome, although none of these syndromes have lissencephaly as a feature.23,25
Synopsis of Treatment Options PRENATAL
Fig. 157.2 Axial T2-weighted image from fetal MRI performed at 28 weeks’ gestation demonstrating the classic hourglass appearance of the brain with agyria and a shallow sylvian fissure (arrow).
findings.6,23,24 In the 29 documented cases of MDS with prenatal findings, polyhydramnios, IUGR, and ventriculomegaly were the most common associated sonographic findings, each seen in approximately 2 out of 3 of cases.13 With the exception of micrognathia, the characteristic facial dysmorphisms are difficult to detect with sonographic imaging.24 Magnetic Resonance Imaging. If abnormal cerebral sulci development is suspected on US, especially in the presence of ventriculomegaly or ACC, fetal magnetic resonance imaging (MRI) can be useful in obtaining a more definitive diagnosis. The appearance of lissencephaly on MRI includes a smooth brain surface with an abnormally shallow sylvian fissure, giving the brain an hourglass or figure-of-eight appearance (Fig. 157.2). These findings are more reliably seen on MRI after 24 weeks’ gestation.3,21,23 MRI may also be more useful in detecting pachygyria as opposed to routine sonography, on which even agyria can be difficult to diagnose.23 Finally, MRI may also aid in detecting and further delineating other associated intra- and extra-cranial malformations.
Differential Diagnosis From Imaging Findings The differential diagnosis of lissencephaly includes the following: • isolated lissencephaly • Norman-Roberts syndrome • Neu-Laxova syndrome
MDS is an incurable syndrome with no known prenatal interventions or treatment options. In cases of a previously affected child or suspicious imaging findings, prenatal diagnosis is available through chorionic villus sampling or amniocentesis. Highresolution chromosomal microarray or fluorescent in situ hybridization (FISH) studies with a LIS1-specific probe can be performed to evaluate for 17p13.3 deletion. Given the uniformly fatal nature of this syndrome, pregnancy termination may be considered. POSTNATAL Currently, there are no gene-specific treatments for lissencephaly. Postnatal management of MDS patients consists mainly of antiepileptics for seizure control and supportive care. Feeding difficulties are common and can be managed with either nasogastric or gastrostomy tubes. Aspiration pneumonia occurs frequently. Affected individuals rarely survive through the second year of life.3,9,26 WHAT THE REFERRING PHYSICIAN NEEDS TO KNOW Suspicion for MDS should be raised in patients with a family history and/or imaging findings concerning lissencephaly. These should prompt both fetal MRI and genetic studies to evaluate for deletions in the 17p13.3 chromosomal region. While routine evaluation of the cerebral sulci is not part of the midtrimester anatomical survey, the presence of ventriculomegaly or other intracranial abnormalities may prompt follow-up imaging at a later gestational age, at which time the sonographic features of lissencephaly may be more prominent.23,25 While the majority of 17p13.3 deletions are de novo, 20% of offspring with MDS inherit the deletion from a parent who carries a balanced chromosomal rearrangement. This warrants parental chromosomal analysis when a diagnosis is made in a child. If neither parent carries the translocation, the risk to subsequent offspring is no greater than that for the background population.27
638
PART 15 Chromosomes • SECTION TWO Deletion Syndromes
KEY POINTS • Miller-Dieker syndrome is a rare contiguous gene deletion syndrome characterized by type 1 lissencephaly, facial dysmorphism, seizures, and profound mental retardation. • Miller-Dieker syndrome is a disorder of impaired neuronal migration and is caused by a deletion at the chromosome 17p13.3 locus. • Characteristic imaging findings on both prenatal US and MRI include a smooth brain surface with an abnormally shallow sylvian fissure, creating an hourglass or figure-of-eight appearance. • Parental chromosomal analysis is indicated at the time of diagnosis, as 20% of deletions are inherited from a parent with a balanced chromosomal rearrangement.
SUGGESTED READING Chen C, Chang T, Guo W, et al. Chromosome 17p13.3 deletion syndrome: aCGH characterization, prenatal findings and diagnosis, and literature review. Gene. 2013;152-159. Fry AE, Cushion TD, Pilz DT. The genetics of lissencephaly. Am J Med Genet C Semin Med Genet. 2014;166C:198-210. Ghai S, Fong FW, Toi A, et al. Prenatal US and MRI imaging findings of lissencephaly: review of fetal and cerebral sulcal development. Radiographics. 2006;26:389-405. Saltzmann DH, Krauss CM, Goldman JM, et al. Prenatal diagnosis of lissencephaly. Prenat Diagn. 1991;11:139-143. Wynshaw-Boris A. Lissencephaly and LIS1: insights into the molecular mechanisms of neuronal migration and development. Clin Genet. 2007;72:296-304.
All references available online at www.expertconsult.com
REFERENCES 1. Miller JQ. Lissencephaly in two siblings. Neurology. 1963;13:841-850. 2. Dieker H, Edwards RH, ZuRhein G, et al. The lissencephaly syndrome. Birth Defects Orig Artic Ser. 1969;5:53-64. 3. Dobyns WB, Curry CJR, Hoyme HE, et al. Clinical and molecular diagnosis of Miller-Dieker syndrome. Am J Med Genet. 1991;48:584-594. 4. Chitayat D, Toi A, Babul R, et al. Omphalocele in Miller-Dieker syndrome: expanding the phenotype. Am J Med Genet. 1997;69:293-298. 5. Chen CP. Syndromes, disorders, and maternal risk factors associated with neural tube defects (V). Taiwan J Obstet Gyencol. 2008;47:259-266. 6. Saltzmann DH, Krauss CM, Goldman JM, et al. Prenatal diagnosis of lissencephaly. Prenat Diagn. 1991;11:139-143. 7. Reiner O, Carrozzo R, Shen Y, et al. Isolation of a Miller-Dieker lissencephaly gene containing G protein beta-subunit-like repeats. Nature. 1993;364: 717-721. 8. Dobyns WB, Reiner O, Carrozzo R, et al. Lissencephaly. A human brain malformation associated with deletion of the LIS1 gene located at chromosome 17p13. JAMA. 1993;270:2838-2842. 9. El Ayoubi M, de Bethmann O. Monset-Couchard M. Lenticulostriate echogenic vessels: clinical and sonographic study of 70 neonatal cases. Pediatr Radiol. 2003;33:697-703. 10. Wynshaw-Boris A. Lissencephaly and LIS1: insights into the molecular mechanisms of neuronal migration and development. Clin Genet. 2007;72:296-304. 11. Dobyns WB, Stratton RF, Greenburg F. Syndromes with lissencephaly 1: Miller-Dieker and Norman-Robert syndromes and isolated lissencephaly. Am J Med Genet. 1984;18:509-524. 12. Dobyns WB, Truwit CL, Ross ME, et al. Differences in the gyral pattern distinguish chromosome 17-linked and X-linked lissencephaly. Neurology. 1999;53:270-277. 13. Chen C, Chang T, Guo W, et al. Chromosome 17p13.3 deletion syndrome: aCGH characterization, prenatal findings and diagnosis, and literature review. Gene. 2013;152-159. 14. Leite JM, Granese R, Jeanty P, et al. Fetal syndromes. In: Callen PW, ed. Ultrasonography in Obstetrics and Gynecology. 5th ed. Philadelphia: Saunders; 2008:151-152.
157 Miller-Dieker Syndrome (17p13.3 Deletion Syndrome) 638.e1 15. Tokuoka SM, Ishii S, Kawamura N, et al. Involvement of platelet-activating factor and LIS1 in neuronal migration. Eur J Neurosci. 2003;18:563-570. 16. Cardoso C, Leventer RJ, Ward HL, et al. Refinement of a 400-kb critical region allows genotypical differentiation between isolated lissencephaly, Miller-Dieker syndrome, and other phenotypes secondary to deletions of 17p13.3. Am J Hum Genet. 2003;72:918-920. 17. Kato M, Dobyns WB. Lissencephaly and the molecular basis of neuronal migration. Hum Mol Genet. 2003;12:R89-R96. 18. Fry AE, Cushion TD, Pilz DT. The genetics of lissencephaly. Am J Med Genet C Semin Med Genet. 2014;166C:198-210. 19. Cardoso C, Leventer RJ, Dowling JJ, et al. Clinical and molecular basis of classical lissencephaly: Mutations in the LIS1 gene (PAFAH1B1). Hum Mutat. 2002;19:4-15. 20. Thomas MA, Duncan AMV, Bardin C, et al. Lissencephaly with der(17) t(17;20)(p13.3;p12.2)mat. Am J Med Genet. 2004;124A:292-295. 21. Herman TE, Siegel MJ. Miller-Dieker syndrome, type 1 lissencephaly. J Perinatol. 2008;28:313-315. 22. Pilz DT, Quarrell OW. Syndromes with lissencephaly. J Med Genet. 1996;33:319-323. 23. Fong KW, Ghai S, Toi A, et al. Prenatal ultrasound findings of lissencephaly associated with Miller-Dieker syndrome and comparison with pre- and postnatal magnetic resonance imaging. Ultrasound Obstet Gynecol. 2004;24: 716-723. 24. McGahan JP, Grix A, Gerscovich EO. Prenatal diagnosis of lissencephaly. J Clin Ultrasound. 1994;22:560-563. 25. Ghai S, Fong FW, Toi A, et al. Prenatal US and MRI imaging findings of lissencephaly: review of fetal and cerebral sulcal development. Radiographics. 2006;26:389-405. 26. Matarese CA, Renaud DL. Classical (type 1) lissencephaly and Miller-Dieker syndrome. Pediatr Neurol. 2009;40:324-325. 27. Hamosh A. Miller-Dieker syndrome. In: Nussbaum RL, McInnes RR, Willard HF, eds. Thompson & Thompson Genetics in Medicine. 7th ed. Philadelphia: Saunders; 2007:288-289.
(17p13.3 Deletion Syndrome) KATHERINE R. GOETZINGER | ALISON G. CAHILL
Introduction Miller-Dieker syndrome (MDS) is a rare, contiguous gene deletion syndrome characterized by type I lissencephaly, facial dysmorphism, seizures, and severe mental retardation.1–3 Other associated defects including cardiac malformations, neural tube defects, omphalocele, gastrointestinal anomalies, genitourinary anomalies, and intrauterine growth restriction have also been described in relationship to this syndrome.3–6 MDS is caused by a deletion at the chromosome 17p13.3 locus and is thought to represent the severe end of the spectrum of classical lissencephaly.7,8 The prognosis for affected patients is poor, with mortality typically occurring within the first 1 to 2 years of life.3,9
Disorder DEFINITION Lissencephaly is a defect in neuronal migration characterized by a smooth cerebral surface, either with agyria (absent gyri) or pachygyria (abnormally broad brain folds), a thickened cerebral cortex, and an increased ratio of gray to white matter. Mutation in the causative LIS1 gene leads to a spectrum of disorders encompassing isolated lissencephaly, subcortical band heterotopia, and MDS.10 Patients with MDS tend to have larger deletions, resulting in more severe lissencephaly in combination with craniofacial dysmorphisms, as well as other associated anomalies.3,11,12 PREVALENCE AND EPIDEMIOLOGY Due to the rarity of disease, the prevalence of MDS is unknown. At least 29 cases of MDS with the 17p13.3 deletion and prenatal findings have been reported in the literature.13 Classical lissencephaly is reported to occur in 11.7–40 : 1 million births.14 ETIOLOGY, PATHOPHYSIOLOGY, AND EMBRYOLOGY Impaired neuronal migration between 6 and 15 weeks’ gestation is the underlying etiologic mechanism for lissencephaly. Postmitotic neurons are unable to migrate to their final destination and therefore do not correctly populate the cortical plate of the cerebral cortex. This leads to the absence of sulci and gyri on the surface of the brain, as well as abnormal cortical thickness. Heterozygous deletions in the region of chromosome 17p13.3 result in the MDS phenotype. Located within this region is the responsible lissencephaly gene (LIS1 or PAFAH1B1), which has been highly conserved throughout evolution. This gene encodes 636
the β subunit of the platelet-activating factor acetylhydrolase brain isoform, which inactivates platelet-activating factor, a neuroregulatory molecule.7,15 While deletions in LIS1 are observed in both isolated lissencephaly and MDS, it is thought that the more severe phenotype observed in MDS is caused by a combined genetic effect from deletions in both LIS1 as well as the YWHAE gene, located about 40 kb telomeric to LIS1 within a region known as the “MDS telomeric critical region.”7,10,16,17 Loss of the YWHAE gene, not including LIS1, results in facial dysmorphism, intrauterine growth restriction (IUGR), and neuroradiologic changes.18 Large deletions that extend farther toward the 17p telomere, including the YWHAE gene, result in the more severe phenotype as observed in MDS.12,17,19 Approximately 80% of patients with MDS have a de novo deletion in the 17p13.3 region, and the remaining 20% are thought to inherit the deletion from a parent who carries a balanced chromosomal translocation.20 MANIFESTATIONS OF DISEASE Clinical Presentation The clinical features of MDS include profound neurodevelopmental delay, seizure activity, failure to thrive, and feeding difficulties. Infants are typically hypotonic at birth and subsequently develop spasticity. The classic facial dysmorphisms include a prominent forehead, low-set ears, widely spaced eyes, a thickened upper lip with a thin vermillion border, an elongated philtrum, a short, upturned nose, bitemporal narrowing, and micrognathia.3,21 Other variable findings include microcephaly, clubfoot, polydactyly, cleft lip/palate, omphalocele, duodenal atresia, hepatosplenomegaly, sacral dimples, joint contractures, hypoplastic genitalia in affected males, and renal and cardiac malformations.3,6,22 Imaging Technique and Findings Ultrasound. The sonographic evaluation for lissencephaly at the time of the midtrimester anatomic survey poses a diagnostic challenge given that brain development and maturation, including formation of normal cerebral gyration, continues throughout gestation. Suspicious sonographic findings include an absent parietooccipital and calcarine fissure as well as a smooth, shallow sylvian fissure, which can be detected in the standard plane used to measure biparietal diameter (Fig. 157.1). These findings have been reported on prenatal ultrasound (US) as early as 23 weeks’ gestation. It is important to note that prior to 20 weeks’ gestation, it is normal for the sylvian fissure to appear as a smooth, shallow depression.23 Other central nervous system (CNS) findings such as ventriculomegaly and agenesis of the corpus callosum (ACC) can be markers for lissencephaly. IUGR and polyhydramnios (secondary to impaired fetal swallowing) are common
157 Miller-Dieker Syndrome (17p13.3 Deletion Syndrome)
A
637
B
Fig. 157.1 (A) Axial ultrasound image at 23 weeks’ gestation demonstrating a shallow/flat sylvian fissure (arrow) in a fetus with Miller-Dieker syndrome. (B) Normal “square” appearance of the sylvian fissure (arrows).
• Walker-Warburg syndrome (type 2) • Fukuyama congenital muscular dystrophy (type 2) • Baraitser-Winter syndrome Other syndromes associated with facial dysmorphisms, seizures, microcephaly, and hypotonia include Cornelia de Lange, WolfHirschorn, Smith-Lemli-Opitz, and Zellweger syndrome, although none of these syndromes have lissencephaly as a feature.23,25
Synopsis of Treatment Options PRENATAL
Fig. 157.2 Axial T2-weighted image from fetal MRI performed at 28 weeks’ gestation demonstrating the classic hourglass appearance of the brain with agyria and a shallow sylvian fissure (arrow).
findings.6,23,24 In the 29 documented cases of MDS with prenatal findings, polyhydramnios, IUGR, and ventriculomegaly were the most common associated sonographic findings, each seen in approximately 2 out of 3 of cases.13 With the exception of micrognathia, the characteristic facial dysmorphisms are difficult to detect with sonographic imaging.24 Magnetic Resonance Imaging. If abnormal cerebral sulci development is suspected on US, especially in the presence of ventriculomegaly or ACC, fetal magnetic resonance imaging (MRI) can be useful in obtaining a more definitive diagnosis. The appearance of lissencephaly on MRI includes a smooth brain surface with an abnormally shallow sylvian fissure, giving the brain an hourglass or figure-of-eight appearance (Fig. 157.2). These findings are more reliably seen on MRI after 24 weeks’ gestation.3,21,23 MRI may also be more useful in detecting pachygyria as opposed to routine sonography, on which even agyria can be difficult to diagnose.23 Finally, MRI may also aid in detecting and further delineating other associated intra- and extra-cranial malformations.
Differential Diagnosis From Imaging Findings The differential diagnosis of lissencephaly includes the following: • isolated lissencephaly • Norman-Roberts syndrome • Neu-Laxova syndrome
MDS is an incurable syndrome with no known prenatal interventions or treatment options. In cases of a previously affected child or suspicious imaging findings, prenatal diagnosis is available through chorionic villus sampling or amniocentesis. Highresolution chromosomal microarray or fluorescent in situ hybridization (FISH) studies with a LIS1-specific probe can be performed to evaluate for 17p13.3 deletion. Given the uniformly fatal nature of this syndrome, pregnancy termination may be considered. POSTNATAL Currently, there are no gene-specific treatments for lissencephaly. Postnatal management of MDS patients consists mainly of antiepileptics for seizure control and supportive care. Feeding difficulties are common and can be managed with either nasogastric or gastrostomy tubes. Aspiration pneumonia occurs frequently. Affected individuals rarely survive through the second year of life.3,9,26 WHAT THE REFERRING PHYSICIAN NEEDS TO KNOW Suspicion for MDS should be raised in patients with a family history and/or imaging findings concerning lissencephaly. These should prompt both fetal MRI and genetic studies to evaluate for deletions in the 17p13.3 chromosomal region. While routine evaluation of the cerebral sulci is not part of the midtrimester anatomical survey, the presence of ventriculomegaly or other intracranial abnormalities may prompt follow-up imaging at a later gestational age, at which time the sonographic features of lissencephaly may be more prominent.23,25 While the majority of 17p13.3 deletions are de novo, 20% of offspring with MDS inherit the deletion from a parent who carries a balanced chromosomal rearrangement. This warrants parental chromosomal analysis when a diagnosis is made in a child. If neither parent carries the translocation, the risk to subsequent offspring is no greater than that for the background population.27
638
PART 15 Chromosomes • SECTION TWO Deletion Syndromes
KEY POINTS • Miller-Dieker syndrome is a rare contiguous gene deletion syndrome characterized by type 1 lissencephaly, facial dysmorphism, seizures, and profound mental retardation. • Miller-Dieker syndrome is a disorder of impaired neuronal migration and is caused by a deletion at the chromosome 17p13.3 locus. • Characteristic imaging findings on both prenatal US and MRI include a smooth brain surface with an abnormally shallow sylvian fissure, creating an hourglass or figure-of-eight appearance. • Parental chromosomal analysis is indicated at the time of diagnosis, as 20% of deletions are inherited from a parent with a balanced chromosomal rearrangement.
SUGGESTED READING Chen C, Chang T, Guo W, et al. Chromosome 17p13.3 deletion syndrome: aCGH characterization, prenatal findings and diagnosis, and literature review. Gene. 2013;152-159. Fry AE, Cushion TD, Pilz DT. The genetics of lissencephaly. Am J Med Genet C Semin Med Genet. 2014;166C:198-210. Ghai S, Fong FW, Toi A, et al. Prenatal US and MRI imaging findings of lissencephaly: review of fetal and cerebral sulcal development. Radiographics. 2006;26:389-405. Saltzmann DH, Krauss CM, Goldman JM, et al. Prenatal diagnosis of lissencephaly. Prenat Diagn. 1991;11:139-143. Wynshaw-Boris A. Lissencephaly and LIS1: insights into the molecular mechanisms of neuronal migration and development. Clin Genet. 2007;72:296-304.
All references available online at www.expertconsult.com
REFERENCES 1. Miller JQ. Lissencephaly in two siblings. Neurology. 1963;13:841-850. 2. Dieker H, Edwards RH, ZuRhein G, et al. The lissencephaly syndrome. Birth Defects Orig Artic Ser. 1969;5:53-64. 3. Dobyns WB, Curry CJR, Hoyme HE, et al. Clinical and molecular diagnosis of Miller-Dieker syndrome. Am J Med Genet. 1991;48:584-594. 4. Chitayat D, Toi A, Babul R, et al. Omphalocele in Miller-Dieker syndrome: expanding the phenotype. Am J Med Genet. 1997;69:293-298. 5. Chen CP. Syndromes, disorders, and maternal risk factors associated with neural tube defects (V). Taiwan J Obstet Gyencol. 2008;47:259-266. 6. Saltzmann DH, Krauss CM, Goldman JM, et al. Prenatal diagnosis of lissencephaly. Prenat Diagn. 1991;11:139-143. 7. Reiner O, Carrozzo R, Shen Y, et al. Isolation of a Miller-Dieker lissencephaly gene containing G protein beta-subunit-like repeats. Nature. 1993;364: 717-721. 8. Dobyns WB, Reiner O, Carrozzo R, et al. Lissencephaly. A human brain malformation associated with deletion of the LIS1 gene located at chromosome 17p13. JAMA. 1993;270:2838-2842. 9. El Ayoubi M, de Bethmann O. Monset-Couchard M. Lenticulostriate echogenic vessels: clinical and sonographic study of 70 neonatal cases. Pediatr Radiol. 2003;33:697-703. 10. Wynshaw-Boris A. Lissencephaly and LIS1: insights into the molecular mechanisms of neuronal migration and development. Clin Genet. 2007;72:296-304. 11. Dobyns WB, Stratton RF, Greenburg F. Syndromes with lissencephaly 1: Miller-Dieker and Norman-Robert syndromes and isolated lissencephaly. Am J Med Genet. 1984;18:509-524. 12. Dobyns WB, Truwit CL, Ross ME, et al. Differences in the gyral pattern distinguish chromosome 17-linked and X-linked lissencephaly. Neurology. 1999;53:270-277. 13. Chen C, Chang T, Guo W, et al. Chromosome 17p13.3 deletion syndrome: aCGH characterization, prenatal findings and diagnosis, and literature review. Gene. 2013;152-159. 14. Leite JM, Granese R, Jeanty P, et al. Fetal syndromes. In: Callen PW, ed. Ultrasonography in Obstetrics and Gynecology. 5th ed. Philadelphia: Saunders; 2008:151-152.
157 Miller-Dieker Syndrome (17p13.3 Deletion Syndrome) 638.e1 15. Tokuoka SM, Ishii S, Kawamura N, et al. Involvement of platelet-activating factor and LIS1 in neuronal migration. Eur J Neurosci. 2003;18:563-570. 16. Cardoso C, Leventer RJ, Ward HL, et al. Refinement of a 400-kb critical region allows genotypical differentiation between isolated lissencephaly, Miller-Dieker syndrome, and other phenotypes secondary to deletions of 17p13.3. Am J Hum Genet. 2003;72:918-920. 17. Kato M, Dobyns WB. Lissencephaly and the molecular basis of neuronal migration. Hum Mol Genet. 2003;12:R89-R96. 18. Fry AE, Cushion TD, Pilz DT. The genetics of lissencephaly. Am J Med Genet C Semin Med Genet. 2014;166C:198-210. 19. Cardoso C, Leventer RJ, Dowling JJ, et al. Clinical and molecular basis of classical lissencephaly: Mutations in the LIS1 gene (PAFAH1B1). Hum Mutat. 2002;19:4-15. 20. Thomas MA, Duncan AMV, Bardin C, et al. Lissencephaly with der(17) t(17;20)(p13.3;p12.2)mat. Am J Med Genet. 2004;124A:292-295. 21. Herman TE, Siegel MJ. Miller-Dieker syndrome, type 1 lissencephaly. J Perinatol. 2008;28:313-315. 22. Pilz DT, Quarrell OW. Syndromes with lissencephaly. J Med Genet. 1996;33:319-323. 23. Fong KW, Ghai S, Toi A, et al. Prenatal ultrasound findings of lissencephaly associated with Miller-Dieker syndrome and comparison with pre- and postnatal magnetic resonance imaging. Ultrasound Obstet Gynecol. 2004;24: 716-723. 24. McGahan JP, Grix A, Gerscovich EO. Prenatal diagnosis of lissencephaly. J Clin Ultrasound. 1994;22:560-563. 25. Ghai S, Fong FW, Toi A, et al. Prenatal US and MRI imaging findings of lissencephaly: review of fetal and cerebral sulcal development. Radiographics. 2006;26:389-405. 26. Matarese CA, Renaud DL. Classical (type 1) lissencephaly and Miller-Dieker syndrome. Pediatr Neurol. 2009;40:324-325. 27. Hamosh A. Miller-Dieker syndrome. In: Nussbaum RL, McInnes RR, Willard HF, eds. Thompson & Thompson Genetics in Medicine. 7th ed. Philadelphia: Saunders; 2007:288-289.