| Cernunnos deficiency | |
| Synonyms: | Combined immunodeficiency-microcephaly-growth retardation-sensitivity to ionizing radiation syndrome, Cernunnos XLFD |
| Symptoms: | Microcephaly |
| Causes: | NHEJ1 gene mutation |
| Diagnosis: | Clinical features |
| Treatment: | Immunoglobulin replacement, HSCT |
Cernunnos deficiency is a form of combined immunodeficiency characterized by microcephaly, due to mutations in the NHEJ1 gene, it is inherited via autosomal recessive manner[1] [2] Management for this condition is antiviral prophylaxis and antibiotic treatment.
The sign and symptoms of this condition on an affected individual are as follows:[2]
In terms of genetics the condition, Cernunnos deficiency is due to a mutation in the NHEJ1 gene, it has a cytogenetic location of 2q35, while its molecular location is 219,075,324 to 219,160,865 [3] [1]
The pathophysiology of Cernunnos deficiency begins with normal function of Non-homologous end-joining factor 1 gene.NHEJ1 encodes a protein which helps repair of breaks in double-stranded DNA. It might additionally act as a connection between XRCC4 and other NHEJ factors (at DNA ends)[4] [3] [5]
When a mutation occurs in NHEJ1, then one sees that nucleotide deletions cause V(D)J recombination, signal joints, to be affected. V(D)J recombination is a genetic recombination that happens in early stages of B and T cell maturation.[6]
The diagnosis of Cernunnos deficiency will find the following in an affected individual via clinical features and blood test:[7] [2]
The DDx for Cernunnos deficiency are both LIG4 syndrome, as well as Nijmegen breakage syndrome[2]
In terms of management for Cernunnos deficiency, one finds that treatment with allogeneic hematopoietic stem cell transplantation, which are stem cells that bring about other cells[8]) has proven useful in some instances. Additionally the following treatments are also used:[9] [2]