What is gene expression ?Watch
DNA to RNA and then to proteins is mostly the initial product formed but not necessarily as it can form other non-coding RNAs as well. these ncRNA (non-coding) are transcribed from DNA but do not translate into proteins. And yes, this could be related to gene expression4
Hope this helped
Gene expression occurs at one or more of several levels:
Transcription (RNA formation)
Postranscriptional modification of RNA
Translation (protein synthesis)
Gene expression (activated by gene promoters or the opposite = gene silencing) is brought about by the regulation of gene expression by transcription factors. The latter bind to DNA sequences in the regulatory regions of genes. e.g. gene silencing can be brought about by methylation of DNA (addition of methyl groups [-CH3]). One other mechanism is the action of a "poly-A tail" (produced by the addition of several adenyl groups), which can modify the transport of mRNA to the cytoplasm, and hence influence translation.
Therefore, No, "it is not a must for proteins to be synthesized".
Google Prader-Willi syndrome, genomic imprinting and the Lyon hypothesis for examples of diseases caused by abnormal gene expression and their explanation.
Hope this helps!
M (specialist biology tutor)