SORCS3 and breast cancer: Second, in spite of the discordance, some of the transcripts within the t-types are expressed in a graded manner and mark the m-types: BCs express Sorcs3; Grm8HIGH; Cacna1eLOW; longer axon SCs in the upper molecular layer express Sorcs3+; Grm8LOW; Cacna1eHIGH; and short-axon SCs express Nxph1. Third, expression of the molecular markers occurs at late stages of MLI development, as MLIs settle at final locations and express Pvalb. BC and SC phenotypes are influenced by laminar locations31,37–40,58, but whether MLI subtype identities diverge at this stage or earlier has not been examined.