- Lissencephaly, also known as smooth brain, is a malformation of the cerebral cortex associated with an abnormal neuronal migration and development of cerebral convolutions or gyri. There can be absent gyri (agyria) or abnormally wide gyri (pachygyria) alongside abnormally thick and poorly organized cortex, diffuse neuronal heterotopia, dysmorphic ventricles and often failure of the corpus callosum to develop. Lissencephaly has been associated with several syndromes and so genetic factors play an important role in its etiology. It is a significant cause of neurological morbidity in children worldwide, responsible for many cases of mental retardation, cerebral palsy, and epilepsy. It is inherited in an autosomal recessive pattern in its majority, although there are forms that are inherited in an autosomal dominant and X-linked fashion.
- The Igenomix Lissencephaly Precision Panel can be used to make a directed and accurate diagnosis ultimately leading to a better management and prognosis of the disease. It provides a comprehensive analysis of the genes involved in this disease using next-generation sequencing (NGS) to fully understand the spectrum of relevant genes involved.
- The Igenomix Lissencephaly Precision Panel is indicated for those patients with head imaging findings (ultrasound, computed tomogram (CT), magnetic resonance imaging (MRI)) suggestive of lissencephaly or with the following manifestations:
- Unusual facial appearance
- Difficulty swallowing
- Failure to thrive
- Muscle spasms
- Severe psychomotor retardation
- Deformed hands, feet or toes
- Microcephaly (small head size)
The clinical utility of this panel is:
- The genetic and molecular confirmation for an accurate clinical diagnosis of a symptomatic patient.
- Early initiation of symptomatic and supportive treatment in the form early referral to a high-risk center, multidisciplinary counselling and close coordination between pediatrics, neurologists and other specialists.
- Risk assessment of asymptomatic family members according to the mode of inheritance.
- Improvement of delineation of genotype-phenotype correlation.
- Identification of the genetic basis of these associated disorders for a better insight into the mechanisms of brain development.
Di Donato, N., Chiari, S., Mirzaa, G. M., Aldinger, K., Parrini, E., Olds, C., Barkovich, A. J., Guerrini, R., & Dobyns, W. B. (2017). Lissencephaly: Expanded imaging and clinical classification. American journal of medical genetics. Part A, 173(6), 1473–1488. https://doi.org/10.1002/ajmg.a.38245
Fry, A. E., Cushion, T. D., & Pilz, D. T. (2014). The genetics of lissencephaly. American journal of medical genetics. Part C, Seminars in medical genetics, 166C(2), 198–210. https://doi.org/10.1002/ajmg.c.31402
Mochida G. H. (2009). Genetics and biology of microcephaly and lissencephaly. Seminars in pediatric neurology, 16(3), 120–126. https://doi.org/10.1016/j.spen.2009.07.001
Mochida G. H. (2008). Brain and nerve = Shinkei kenkyu no shinpo, 60(4), 437–444.
Romero, D. M., Bahi-Buisson, N., & Francis, F. (2018). Genetics and mechanisms leading to human cortical malformations. Seminars in cell & developmental biology, 76, 33–75. https://doi.org/10.1016/j.semcdb.2017.09.031
Parrini, E., Conti, V., Dobyns, W. B., & Guerrini, R. (2016). Genetic Basis of Brain Malformations. Molecular syndromology, 7(4), 220–233. https://doi.org/10.1159/000448639