These are the altered Neighborhood files for Strangetown and Veronaville.  I only had the base game installed so there is no EP interference.
Only use on an unplayed neighborhood.  If you are a frequent neighborhood-restarter you can place the file in Programs/EAGames/TS2/TSData/Res/UserData/Neighborhoods/N00#.  # is replaced by 2 for Strangetown and 3 for Veronaville.  Dont forget to place each time you do a total uninstall/reinstall though.
You should also place this file in the corresponding Neighborhood folder to overwrite game generated Neighborhood file at least the first time. The location is MyDocuments/EaGames/TS2/Neighborhoods/N00#.
You only need one file for each Neighborhood, heterozygous or homozygous
To create the Homozygous files all I did was copy and paste.
example: Brad has Dark Blue eyes, Blonde Hair and tan skin.
Old SDNA:
Dominant Gene:
   Eye      2d6839c5-0b7c-48a1-9c55-4bd9cc873b0f
   Facial Feature   brow,mouth,cheekbones,ears,
   Hair      00000003-0000-0000-0000-000000000000
   Skintone
   SkintoneRange   00000002-0000-0000-0000-000000000000
Recessive Gene:
   Eye      2d6839c5-0b7c-48a1-9c55-4bd9cc873b0f
   FacialFeature
   Hair      00000003-0000-0000-0000-000000000000
   Skintone
   Skintone Range   00000002-0000-0000-0000-000000000000
New SDNA:
Dominant Gene:
   Eye      2d6839c5-0b7c-48a1-9c55-4bd9cc873b0f
   Facial Feature   brow,mouth,cheekbones,ears,
   Hair      00000003-0000-0000-0000-000000000000
   Skintone      00000002-0000-0000-0000-000000000000
   SkintoneRange   00000002-0000-0000-0000-000000000000
Recessive Gene:
   Eye      2d6839c5-0b7c-48a1-9c55-4bd9cc873b0f
   FacialFeature
   Hair      00000003-0000-0000-0000-000000000000
   Skintone      00000002-0000-0000-0000-000000000000
   Skintone Range   00000002-0000-0000-0000-000000000000
To do a Heterozygous one I looked at everyones dna, so that sims would have dna that reflects their parentage.
Example: Bob has Dark Blue eyes, Black Hair and medium skin.  Betty had grey eyes, blonde hair and tan skin.  Their daughter Brandi has Dark Blue Eyes, Blonde hair and tan skin.
Old SDNA:
Dominant Gene:
   Eye      2d6839c5-0b7c-48a1-9c55-4bd9cc873b0f
   Facial Feature   brow,mouth,cheekbones,ears,
   Hair      00000003-0000-0000-0000-000000000000
   Skintone      00000002-0000-0000-0000-000000000000
   SkintoneRange   00000002-0000-0000-0000-000000000000
Recessive Gene:
   Eye      2d6839c5-0b7c-48a1-9c55-4bd9cc873b0f
   FacialFeature
   Hair      00000003-0000-0000-0000-000000000000
   Skintone      00000002-0000-0000-0000-000000000000
   Skintone Range   00000002-0000-0000-0000-000000000000
New SDNA:
Dominant Gene:
   Eye      2d6839c5-0b7c-48a1-9c55-4bd9cc873b0f
   Facial Feature   brow,mouth,cheekbones,ears,
   Hair      00000003-0000-0000-0000-000000000000
   Skintone      00000002-0000-0000-0000-000000000000
   SkintoneRange   00000002-0000-0000-0000-000000000000
Recessive Gene:
   Eye      0758508c-7111-40f9-b33b-706464626ac9
   FacialFeature
   Hair      00000001-0000-0000-0000-000000000000
   Skintone      00000003-0000-0000-0000-000000000000
   Skintone Range   00000003-0000-0000-0000-000000000000
 Original Thread is 
http://www.moreawesomethanyou.com/smf/index.php?topic=1423.0