34. Cancer causing genes can be functionally classified into mainly three types: (i) genes that induce cellular proliferation, (ii) tumor suppressor genes, (iii) genes that regulate apoptotic pathway. Epstein-Barr virus that causes cancer by modulating apoptotic pathway, contains a gene having sequence homology with which of the following genes?
    (1) bax (2) bcl-2
    (3) p53 (4) caspase-3

The Epstein-Barr virus (EBV), known for causing cancer by modulating the apoptotic pathway, contains a gene with sequence homology to:

(2) bcl-2

Explanation

• EBV encodes BHRF1, a viral homologue of the anti-apoptotic cellular gene bcl-2. This viral Bcl-2 homologue inhibits apoptosis by preventing activation of the intrinsic apoptotic pathway, contributing to cell survival and oncogenesis.​

• The viral Bcl-2-like protein helps infected cells evade programmed cell death, aiding in cell transformation and cancer progression.

• Other apoptosis-related genes mentioned, like bax, p53, or caspase-3, are not directly encoded by EBV.