The scientists have recently expanded the Delta family from four to 13 variants. While a few of the variants are being “reclassified” to another sub-lineage — AY.12, it has been reported that a large number of the same variant-caused cases have been prevalent in Israel. The India SARS-CoV-2 Genome (INSACOG) consortium reported the same after tracking the variant. 

“However, since the AY.12 definition is inconsistent, final numbers will take some time,” a statement by the consortium read.

What is this AY.12 mutation?

It is no secret that as the virus travels through the body, it makes copies of itself, with rather minute changes.

Similarly, the Delta variant (B.1.617.2) has resulted in a variety of sub-lineages called ‘Delta Plus’ variants, which are similar to the parent variant in many ways. However, there are a few differences in their characteristic mutations. One of these sub-lineages, AY.12 has all characteristic Delta mutations except one.

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The concerning spike in cases in Israel is despite nearly 60% of its adults being fully vaccinated. “The reclassification is primarily to assist micro-epidemiology and is not based on acquisition of significant mutations. Thus, it is not currently known whether AY.12 is clinically different from Delta,” the INSACOG report noted. “No new mutations of concern are noted in the spike protein (S). However, its rapid growth in Israel means that it should be examined further.”

According to INSACOG, it is still unknown whether AY.12 is clinically different from Delta or B.1.617.2.

However, AY.12 is without G142D in spike protein. AY.12 is much more prevalent in Israel with 51% of samples showing its presence.  The prevalence has even reportedly increased over 20%.

While asking states to maintain caution and look out for this variant, INSACOG said: “AY.12, a reassigned sub-lineage of Delta is being seen in many states, but the numbers need closer examination. The functional impact of the changes between Delta and AY.12 is not known but the two appear to be very similar at a molecular level.”