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Genetics
- Ad-mixture (aka Ethnicity Mix)
- Allosomes (Sex chromosomes X & Y)
- Autosomes (Chromosomes 1-22)
- Base Pair
- CE Testing (1st Wave)
- centiMorgan (cM)
- Chromosomes
- Clade
- Cladogram
- dbSNP, rsID, NIH, etc
- Deoxyribonucleic Acid (DNA)
- Derived & Ancestral
- Endogamy or Pedigree Collapse
- epigenetics
- Gene
- Genetic Marker
- Genome Build (aka Reference Model)
- Genotyping
- Haplogroup
- Haploid & Diploid
- Haplotype
- Imputation
- Low Coverage Sequencing
- Meiosis & Mitosis
- Microarray Testing (2nd Wave)
- Microarray File Formats (aka RAW)
- Mito Build (rCRS, Yoruba, RSRS)
- Mitochondria
- Modal
- Null Allele
- Pangenome
- Phylogenetic Tree
- Probes, Primers, Adaptors and Tags
- Recombination (aka Cross-Overs)
- Sampling Techniques
- Sequencing (3rd Wave)
- Sequencing File Formats
- Single Nucleotide Polymorphism (SNP)
- Short Tandem Repeat (STR)
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Genealogy
- Ahnentafel number
- Ancestor and Descendant
- Birth, Marriage and Death (BMD)
- Branches
- Consanguinity
- Cousins
- Deep Ancestry
- Earliest Known Ancestor (EKA)
- Family (Nuclear, and Household)
- Genealogical Exchange Database (GEDCom)
- Genealogical Proof Standard (GPS)
- Genealogical Records
- Genealogical Time Frame (aka last 500 years)
- Genealogical Tool
- Genealogical Trees
- Generation Difference (GD)
- Individuals
- Most Recent Common Ancestor (MRCA)
- Née
- Not Parent Expected (NPE)
- One-Tree (aka World Tree)
- Patriline & Matriline
- Places
- Repositories
- Siblings
- Sources
- Surname, One-Name and Family Branch Studies
- Years Before Present (ybp)
- (Genetic Genealogy) Terms
- Genetics Industry
- (Genetic Genealogy and Ancient DNA) Industry
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- centiMorgan (cM)
A centiMorgan (or cM for short) is a measure of a matching segment length in genetic genealogy. It is a more accurate measure of the real, respective length of a segment than the raw base-pair count. This because the segment length is being determined from the sparsely measured SNPs which are not evenly scattered among the DNA strands. Thus the cM is an adjusted length based on the frequency of occurring SNPs that happen to be measured. It is also based on the propensity of a given area to be split, during recombination, into a smaller segment.
Each testing company reports a different number of cM's. To determine the half-identical, or roughly haploid amount, look at the total matching length between a mother and daughter. (Or less accurately any parent and child. We restrict it here as some companies include X matching in their reported length. Reported total cM's for a fully-matching,half-identical match are often higher than the actual base-pair count but very roughly correspond to millions of base-pairs. That is, 1 cM is roughly equivalent to 1,000,000 base-pairs when looking at the whole genome.
Each testing company reports a different number of cM's. To determine the half-identical, or roughly haploid amount, look at the total matching length between a mother and daughter. (Or less accurately any parent and child. We restrict it here as some companies include X matching in their reported length. Reported total cM's for a fully-matching,half-identical match are often higher than the actual base-pair count but very roughly correspond to millions of base-pairs. That is, 1 cM is roughly equivalent to 1,000,000 base-pairs when looking at the whole genome.