Splice Variants of GPCRs

Table 1.

Splice Variation and Complexity of GPCR-EncodingGenes

GPCR	Number of Introns	Number of Reported Splice Variants
^a Comparison of gene structure and number of splice variants for a subset of human GPCRs whose gene structures have been reported. The number of human splice variants reported to date (February, 2001) and presented above is in addition to the original cDNA sequence and excludes variants predicted to contain fewer than seven transmembrane domains. The number of introns in the primary open reading frame (ORF) was determined from the genomic structure of the first reported cDNA, and does not include introns between alternatively spliced C-terminal exons. An expanded version of this Table with references is available in the online version.
CLASS A
adenosine A₁, A_2a, A_2b, A₃	1	0
adrenergic β₁, β₂, α_{2A, B, C}	0	0
adrenergic β₃	1	0
adrenergicα _1A	1	3
dopamine D₁,D₅	0	0
dopamine D₂	6	1
histamine H₁,H₂	0	0
histamine H₃	2	2
muscarinic m_1,2,3,4,5	0	0
opioid mu	2	6
opioid delta	2	0
purinergic P2Y_1,2,4,6	0	0
rhodopsin	4	0
serotonin 5HT_{1A,1B,1D,1E,1F}	0	0
serotonin 5HT_2A,B	2	0
serotonin 5HT₄	6	6
CLASS B
CRFR2	12	2
Secretin	12	0
CLASS C
GABA_B-R₁	21	2
mGluR6	9	0