Microcephaly is generally defined as a small head size, typically greater than two standard deviations below normal, as measured via occipital frontal circumference, using a measuring tape. Microcephaly is a clinical sign and not a disease. It is the result of a premature fusion of the skull sutures that leads to an abnormal shape and a growth limitation of the head circumference that can later result in long term neurological sequelae. The cause of microcephaly can be divided in two groups: premature fusion of cranial sutures, also known as craniosynostosis or poor brain growth. Genetic conditions are one of the etiologies of microcephaly and include: Trisomy 21, 13, 18, Cri Du Chat syndrome, Williams syndrome etc. Also, inborn errors of metabolism, disruptive injuries and maternal deprivation problems can lead to microcephaly. Primary microcephaly is usually inherited in an autosomal recessive pattern.
The Igenomix Primary Microcephaly Precision Panel can be as a diagnostic tool to reveal underlying genetic conditions 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, and their high or intermediate penetrance.
- The Igenomix Primary Microcephaly Precision Panel is indicated in those cases where there is:
- Head circumference more than 2 standard deviations below the mean
- Consistent low percentile of head circumference ultrasound measurements during pregnancy
- Associated syndromic features: congenital heart defects, umbilical hernia, hypotonia, low set ears, short neck, overlapping fingers, micrognathia, polydactyly etc
The clinical utility of this panel is:
- The genetic and molecular diagnosis for an accurate clinical diagnosis of microcephaly as well as underlying genetic conditions.
- Early initiation of treatment with a multidisciplinary team for appropriate surveillance, surgical care and long-term monitoring to ensure proper cerebral and cranial growth.
- Risk assessment and genetic counselling of asymptomatic family members according to the mode of inheritance.
- Improved pathways from diagnosis to treatment in susceptible populations.
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