In what could be called a major breakthrough, scientists claim to have identified a gene which is linked to birth defects in many individuals. Also, they have identified three new genes which are linked to throat cancer.
An international team, led by Leeds University, has, in fact, found the genetic cause of inherited conditions — Meckel-Gruber syndrome and Joubert syndrome — that causes severe foetal abnormalities, the Nature Genetics reported.
Meckel-Gruber syndrome and Joubert syndrome are part of a wider family of disorders known as “ciliopathies” — so called because the cilia are not working as they should and don’t respond properly to signals.
This lack of communication can prevent the neural tube from developing correctly in growing embryos, leading to abnormalities in the brain. Affected embryos can also develop abnormalities in the eyes, extra fingers or toes, and multiple cysts in their kidneys, say the scientists.
To find the gene responsible for Meckel-Gruber and Joubert syndromes, the scientists examined DNA from families with a history of the disorder, from skin cells donated by patients, and from cells grown in the laboratory.
They also studied zebrafish, which have very visible embryos.
The work identified a previously unknown gene — TMEM216 — as a cause of Meckel-Gruber and Joubert syndromes.
They also showed that the faulty TMEM216 gene stopped cells from making a protein that is needed for signalling.
Meanwhile, an international team, led by the Genome Institute of Singapore, identified genetic risk factors of nasopharyngeal carcinoma (NPC) that advance the understanding of the role played by host genetic variation in influencing susceptibility to this type of throat cancer.
NPC is a type of cancer that forms in the epithelial lining of the nasopharynx, the area of the upper throat that lies behind the nose.
To search for the genetic risk factors for NPC, the scientists carried out a comprehensive genetic analysis of the human genome in a large clinical sample of southern Chinese descent — approximately 5,000 patients and 5,000 controls.
The team found that the genetic variation within the human leukocyte antigen (HLA) and the three genes known as TNFRSF19, MDSIEVI1 and CDKN2A/2B can significantly influence a person’s risk of developing NPC.
The scientists also noticed that these three susceptibility genes for NPC have been reported to be involved in the development of leukaemia, suggesting there might be some shared biological mechanism between the developments of these two diseases.