OMIM- Online Mendelian Inheritance in Man

It is a comprehensive, authoritative and timely knowledgebase of human genes and genetic disorders compiled to support human genetics research and education and the practice of clinical genetics.
One of the best websites for detailed and updated information of genetic diseases.
Set up in 1995 by the National Centre for Biotechnology Information (NCBI).

1. Online Mendelian
Inheritance in Man
OMIM Database

2. Introduction
•Itisacomprehensive,authoritativeandtimely
knowledgebaseofhumangenesandgeneticdisorders
compiledtosupporthumangeneticsresearchandeducation
andthepracticeofclinicalgenetics.
•Oneofthebestwebsitesfordetailedandupdatedinformation
ofgeneticdiseases.
•Setupin1995bytheNationalCentreforBiotechnology
Information(NCBI).

3. DISORDERS DEALT WITH IN OMIM
•ContainsdisorderswhichareinheritedinaMendelianfashion.
•Itdoesnotincludeconditionsresultingfromchromosomalaberrations.
•Forexample:Informationaboutallgeneticskindiseasesand
syndromesuchastheichthyosis,epidermolysisbullosa,
neurofibromatosisandlipoidproteinosis.
•Immunologicalorinflammatorydisorderswithapolygenicinheritance
suchasatopicdermatitis,psoriasisetc.arealsoincluded.

4. OMIM NUMBERS
EachgeneticdisorderhasbeenallottedauniquesixdigitOMIM
number.Thefirstdigitindicatesthemodeofinheritanceofthedisorder,
viz.
1.(100000-)Autosomaldominantlociorphenotypes
2.(200000-)Autosomalrecessivelociorphenotypes
3.(300000-)X-linkedlociorphenotypes
4.(400000-)Y-linkedlociorphenotypes
5.(500000-)Mitochondriallociorphenotypes
6.(600000-)Autosomallociorphenotypes

5. HOW IS A DISEASE ACCESSED ON OMIM?
•Thebasicsearchinvolvestypinginthenameofadisease,a
chromosomenumberoragenesymbol,andclickingon‘Go’.
•Infact,almost1900entriesshowupfortheword‘skin’,givingone
someideaofhowmanygeneticdisordersinvolvetheskin.
•Forexample,asearchfor‘dermatitis’showsabout226entrieswhich
includevarioussubtypesofdermatitisandrelatedgeneticconditions.

6. OMIM GENE MAP & OMIM MORBID MAP
TheOMIMgenemaplistsdisordersgenewise,startingwith
chromosome1pandendingwith22q,alongwiththeXandY
chromosomes.Diseaseswhichhavebeenlinkedtospecificgeneson
thesechromosomesareavailableinthismap.Thismapcanbesearched
usingthechromosomenumber,genesymbolornameofdisorder.
TheOMIMmorbidmapisanalphabeticallistofdisordersandtheir
cytogeneticlocations.Itcanbesearchedinthesamefashionasthe
OMIMgenemap.

7. OTHER FEATURES
•AclickonOMIMstatisticsletsoneknowthetotalnumberof
entriesavailableonthatday.
•Thewebsitealsoprovidesdetailsofchanges,additionsand
deletionsonamonthlybasissinceitsinceptionin1995.
•OMIMalsoprovideslinkstoPubmed,theHumanGenome
websitesandotherrelatedgeneticresearchwebsites.

8. WHAT DOES OMIM NOT PROVIDE?
•OMIMdoesnothaveacompletelistofallgeneticdisorderscontained
init;thesehavetobesearchedbynameorsymbol.
•Italsodoesnotprovidefacilitiesfortheclinicalevaluationandgenetic
testingofpatientsofsuspectedgeneticdiseases.
•Forthesetypesofqueriesandinformation,othersourcessuchas
GeneticAlliance,NORD(NationalOrganizationforRareDisorders)
andGeneTestsmaybeuseful.