In principle, the code attribute should designate the type of the genetic variation being described in this

Clinical Genomic Statement. Typically, a genetic variation can be characterized by multiple aspects, e.g.,

DNA change, amino acid change, Transcript Reference Sequence Identifier, etc. It is important to note that

there is no single standard for any type of genetic variation and even HGVS nomenclature doesn't cover all

cases. Also, 'gene-centric' variation notations might be disadvantageous because in some genomic locations, a

variant may be influencing several genes (or transcripts of the same gene) and may have different effects, for

example, an indel in an intron of one transcript may be a frame shift in an exon of another transcript for the

same gene.

When possible, a coded panel of such characteristics should be used, for example, the LOINC panel "DNA

Analysis Discrete Sequence Variant Panel" (code=55208-3) designed for clinical environment. When this code

is assigned to the code attribute, then this Clinical Genomic Statement SHALL consist of nesting observations

describing the Gene Identifier, Transcript Reference Sequence Identifier, DNA Sequence Variation, DNA

Sequence Variation Type, Amino Acid Change, Amino Acid Change Type, DNA Region Name, Allelic

State, Genomic Source Class. The constraining of these nesting observations are described in detail in the

associations of this Clinical Genomic Statement, including their code and binding value sets.

If code is not assigned with the above-mentioned LOINC Panel, then it should use either the Human Genome

Variation Society (HGVS) nomenclature (identified as HGNC with OID = 2.16.840.1.113883.6.281) or other

recognized notation of genetic variations (that can be uniquely identified).

If code=55208-3 (LOINC code for "DNA Analysis Discrete Sequence Variant Panel"), then value SHALL

NOT be used. (CONF-GTR-91)