anchor.diff:      (protein-features transl (symbol-name feat-type))))
   
   (defun protein-features (protein &optional feat-type)
  +  "Returns all sequence properties of a protein.
  +
  +Example:
  +
  +* (defparameter *ts* (car (transcripts (sample-gene-rhodopsin))))
  +* (defparameter *tl* (translation *ts*))
  +* (protein-features *tl*)
  +(#<PROTEIN-FEATURE {BA8CEB1}> #<PROTEIN-FEATURE {BA8D719}>
  +        ...
  +		 #<PROTEIN-FEATURE {BA9DC01}> #<PROTEIN-FEATURE {BA9E481}>)
  +"
     (protein-features-of-type protein feat-type))
   
   
   (defun protein-feature-type (pf)
  +  "Returns the type of a particular feature. This information can be used to filter the retrieval of features, e.g., with the protein-features-of-type method.
  +
  +Example: 
  +
  +* (defparameter *ts* (car (transcripts (sample-gene-rhodopsin))))
  +* (defparameter *tl* (translation *ts*))
  +* (protein-features *tl*)
  +* (defparameter *ts* (car (transcripts (sample-gene-rhodopsin))))
  +* (defparameter *tl* (translation *ts*))
  +* (mapcar #'protein-feature-type (protein-features *tl*))
  +
  +* (mapcar #'protein-feature-type (protein-features *tl*))
  +
  +(\"Pfam\" \"Pfam\" \"Superfamily\" \"transmembrane\" \"transmembrane\"
  + \"transmembrane\" \"transmembrane\" \"transmembrane\" \"transmembrane\"
  + \"transmembrane\" \"low_complexity" "Prosite_patterns" "Prosite_patterns\"
  + \"Prosite_profiles\" \"Prints\" \"Prints\" \"Prints\" \"Prints\" \"Prints\"
  + \"Prints\" \"Prints" \"Prints\" \"Prints\" \"Prints\" \"Prints\" \"Prints\"
  + \"Prints\" \"Prints\" \"Prints" \"Prints\" \"Prints\" \"Prints\" \"Prints\"
  + \"Prints\")"
     (slot-value (analysis pf)
                 'db))
   
  
positive.code:   "The length of the sequence on the genome.
  
  ###Example:
  (seq-length (fetch-by-stable-id \"ENSG00000141510\")) "
    (with-slots ((seq-start seq-region-start)
                 (seq-end   seq-region-end))
        ens-obj
  
negative.code: (defgeneric transmembrane-protein-p (transcript-or-protein)
    (:documentation "Returns T iff the given protein (or the protein
  resulting from translating the transcript) contains a transmembrane
  region as stored in Ensembl and predicted by TMHMM.
  
  Example:
  
  * (transmembrane-protein-p (car (transcripts (sample-gene-rhodopsin))))
  
  T")
    (:method ((trans (eql nil))) nil)
    (:method ((tl translation)) 
      (not (null (protein-features tl "transmembrane"))))
  