Sudden death of an infant with cardiac, nervous system and genetic involvement--a case report

Comprehensive Analysis of Genes Associated With Sudden Infant Death Syndrome

Background: Sudden infant death syndrome (SIDS) is a tragic incident which remains a mystery even after post-mortem investigation and thorough researches. Methods: This comprehensive review is based on the genes reported in the molecular autopsy studies conducted on SIDS so far. A total of 20 original studies and 7 case reports were identified and included in this analysis. The genes identified in children or adults were not included. Most of the genes reported in these studies belonged to cardiac channel and cardiomyopathy. Cardiac channel genes in SIDS were scrutinized for further analysis. Results: After screening and removing the duplicates, 42 unique genes were extracted. When the location of these genes was assessed, it was observed that most of these belonged to Chromosomes 11, 1 and 3 in sequential manner. The pathway analysis shows that these genes are involved in the regulation of heart rate, action potential, cardiac muscle cell contraction and heart contraction. The protein-protein interaction network was also very big and highly interactive. SCN5A, CAV3, ALG10B, AKAP9 and many more were mainly found in these cases and were regulated by many transcription factors such as MYOG C2C1 and CBX3 HCT11. Micro RNA, "hsa-miR-133a-3p" was found to be prevalent in the targeted genes. Conclusions: Molecular and computational approaches are a step forward toward exploration of these sad demises. It is so far a new arena but seems promising to dig out the genetic cause of SIDS in the years to come.

A Systematic Review of Molecular Autopsy Studies in Sudden Infant Death Cases

Sudden unexpected death is an upsetting event, which can remain unexplained even after post-mortem investigation. Internationally, molecular autopsies have shown to resolve up to 44% of unexplained cases; however, it is currently unclear how many of these were infants. This systematic literature review showed that significantly fewer infant cases were resolved (median: 4%) compared with cohorts of 1 to 45 years old (median: 32%). Further, no study involving indigenous African participants has yet been published. Overall, molecular autopsies hold immense value to living family members and is motivation to explore new avenues in infant cohorts.

The mesencephalic nucleus of the trigeminal nerve and the SIDS

Sudden infant death syndrome (SIDS) is a major cause of infant mortality throughout the world, yet its cause and mechanism of action remain poorly understood. Here, we discuss a novel model of the etiology of SIDS which ties together what is known about the brain regions thought to be affected in SIDS infants with a defined neuroanatomical circuit and a documented preventative factor in young children. We propose that SIDS occurs due to a lack of sufficient development and plasticity of glutamatergic synapses in the mesencephalic nucleus of the trigeminal nerve (Me5) and reticular formation (RF) of the brainstem. This model is supported by evidence of brainstem dysfunction in SIDS as well as evidence of signaling through the Me5 and RF in another means of regulating cortical arousal. Furthermore, long-term plasticity of glutamatergic synapses is well known to play a critical role in learning and memory in other regions of the brain, implying that those mechanisms may also be relevant in the development of brainstem circuitry. This model clearly explains why SIDS deaths appear so suddenly with little pathological explanation and suggests a potentially novel way to prevent these deaths from occurring.