{"id":4156,"date":"2016-06-03T18:14:51","date_gmt":"2016-06-03T18:14:51","guid":{"rendered":"http:\/\/labgenvet.ca\/en\/?page_id=4156"},"modified":"2023-07-11T18:14:36","modified_gmt":"2023-07-11T18:14:36","slug":"cat-genetics-1-0-basics","status":"publish","type":"page","link":"https:\/\/labgenvet.ca\/en\/cat-genetics-1-0-basics\/","title":{"rendered":"Cat Genetics 1.0: The Basics"},"content":{"rendered":"

[vc_row][vc_column][vc_column_text]<\/p>\n

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Cat Genetics 1.0: The Basics<\/h1>\n

\"\"<\/a>Cat owners, cat breeders and veterinarians with cat practices should all have a basic understanding of cat genetics. \u00a0Intuitively it is quite simple, and it\u2019s all about two.\u00a0 Two parents, but you already know that. \u00a0Two copies of every gene.\u00a0 Two copies of every chromosome. The number to remember is two.\u00a0 Cat genetics doesn\u2019t get any simpler than this, and what is more, it\u2019s the same simplicity at the root of our genetics. \u00a0Unfortunately, simplicity plus simplicity plus simplicity \u2026\u2026 can quickly give us complexity.\u00a0 But we\u2019ll try to keep it simple.<\/p>\n

The Cat’s Genome<\/h3>\n
\"\"<\/a>
Maine Coon kitten<\/span><\/div><\/div>\n

Think of genes<\/strong> as little biological paragraphs in a book.\u00a0 Each paragraph serves a function; it is biological information with something to say. \u00a0It is a set of biological instructions.\u00a0 Now think of chromosomes<\/strong> as groups of paragraphs that make up the chapters of the book.\u00a0\u00a0 Think of the book as all the paragraphs (genes) and all the chapters (chromosomes) put together.\u00a0 Let\u2019s call the book the genome<\/strong>.\u00a0 The genome is a very special book, a recipe book filled with sets of instructions that collectively tell a story.\u00a0 Think of the genome as a recipe book, something like a fusion between \u2018The Joy of Cooking\u2019 and \u2018The Joy of Sex\u2019, but much more clever. \u00a0Now think of the genome as a double set of instructions since in genetics, everything (parents, genes, chromosomes) comes in twos.<\/p>\n

The cat\u2019s genome tells a very good story. First of all it tells how to make a cat. Then it tells how to be a cat.<\/p>\n

The biochemical alphabet of life<\/h3>\n

Genes are written in a special text called \u2018bases<\/strong>\u2019.\u00a0 Bases are the biochemical alphabet of life, and there aren\u2019t very many of them, only four: A<\/strong>, C<\/strong>, G<\/strong>, and T<\/strong>. \u00a0Simple, right?\u00a0 But remember, simplicity plus simplicity plus simplicity \u2026\u2026 eventually gives us complexity.\u00a0 It\u2019s like electricity, where the two conditions of current \u2018on\u2019 and current \u2018off\u2019 can eventually give us the internet.\u00a0 Or like the 26 letters of our English alphabet that can eventually give us \u2018Hamlet\u2019 or \u2018Dubliners\u2019.<\/p>\n

Back to the bases A, C, G and T.\u00a0 The bases are lined up one after the other, hundreds, thousands, millions of them, like beads on a string and making a special necklace.\u00a0 The necklace is our DNA<\/strong>.<\/p>\n

In the laboratory we have learned how to read the bases that make up the genes that make up our genomes.\u00a0 We can read our DNA.\u00a0 We can read our cat\u2019s DNA.\u00a0 We can read the alphabet of life.\u00a0 And even understand a little bit of it\u2019s logic.<\/p>\n

 <\/p>\n

Oh what clever apes are we<\/strong><\/p>\n

To know the alphabet of life<\/strong><\/p>\n

To read our genes: A, C, G, T<\/strong><\/p>\n

What power.\u00a0 What humility.<\/strong><\/p>\n

 <\/p>\n

An example Cat Sequencing Profile<\/h3>\n

Here is a sequencing profile at the site of a mutation that causes a retinal degeneration disease in cats (PRA-rDAc). \u00a0The sequencing profile actually represents both copies of the gene in question, one superimposed upon the other.\u00a0 The shaded base (T) indicates that the cat has two normal copies of the gene in question.\u00a0 If a copy of the gene was mutated it would show up as a G.<\/p>\n

\"Genetics<\/p>\n

 <\/p>\n

The Genome as a Deck of Cards<\/h3>\n

Back to the genome.\u00a0 The genome contains biological information.\u00a0 How to transfer this information from one generation to the next?\u00a0 Once again, intuitively we know: this time it\u2019s all about sex.\u00a0 Now think of the genome as a deck of cards. Actually a double deck of cards: everything comes in twos, remember? \u00a0Let\u2019s say that Dad has a genome consisting of only black cards and that Mom has a genome consisting of only red cards.\u00a0 Each parent now shuffles their cards (their genome), and then cuts their deck in two so that only half of their cards will get passed to the next generation.\u00a0 Sex happens.\u00a0 The resulting offspring (kittens in this example) will now have a new genome consisting of a full (double) deck of cards, half of which are black (from Dad), the other half of which are red (from Mom).<\/p>\n

\"Cards<\/a><\/p>\n

Dominant and Recessive Traits<\/h3>\n

The fact that genes come in pairs (one copy from each parent) is a good thing as it allows biology to experiment with genetics and thus allows animals to evolve and become (just for example) cats.\u00a0 But it can also be not so good in that bad copies of genes can stay hidden.\u00a0 A healthy cat can be a carrier for disease genes.\u00a0 If two healthy (carrier) cats are mated they can have kittens that are diseased, and other kittens that are healthy.\u00a0 \u00a0And that\u2019s at the heart of heredity.<\/p>\n

Let\u2019s look at an example of heredity.\u00a0 Consider a black cat (presence of pigment) and a white cat (absence of pigment).\u00a0 Let\u2019s say that white is the recessive<\/strong> trait, i.e. can be hidden, and that black is the dominant<\/strong> trait, i.e. always reveals itself.\u00a0 Let\u2019s call the gene responsible for the presence (or absence) of pigment the gene \u2018C\u2019.\u00a0 Furthermore, let\u2019s call the black version of the gene capital \u2018C\u2019, and the white version of the gene small \u2018c\u2019.<\/p>\n

Now go back to the idea that you have two parents and that everything in genetics comes in pairs.\u00a0 To have a white cat, we need two white copies of the gene for pigmentation (cc).\u00a0 To have a black cat we only need to have one black copy of the gene for pigmentation, while the other copy can be for black or for white (CC or Cc).\u00a0 CC will give us a black cat that is \u2018clear\u2019 (not a carrier) for the white copy of the gene.\u00a0 Cc will give us a black cat that is a carrier for the white copy of the gene.<\/p>\n

We now look at three possibilities for mating our black and white cats:<\/p>\n

\"Pedigrees-cat\"<\/a><\/p>\n

Black X White (‘Clear’ X Affected)<\/strong>
\nThis will give all black kittens.\u00a0 All the kittens will be carriers for white.<\/p>\n

Black X White (Carrier X Affected)<\/strong>
\nThis will give black kittens and white kittens, in about equal numbers.\u00a0 The black kittens will be carriers for white.<\/p>\n

Black X Black (Carrier X Carrier)<\/strong>
\nThis will give black kittens and white kittens, but more black than white.\u00a0 Some of the black kittens will be \u2018clear\u2019, while some of them will be carriers for white.<\/p>\n

Once again, genetics doesn\u2019t get any simpler than this.\u00a0 Once again, it can get more complicated. \u00a0For more comprehensive explanations of basic genetics and the genetics for cats there is a lot of information available only a few taps away on the internet:<\/p>\n

https:\/\/en.wikipedia.org\/wiki\/Genetics<\/a><\/p>\n

https:\/\/en.wikipedia.org\/wiki\/Cat_coat_genetics<\/a><\/p>\n

http:\/\/messybeast.com\/colour-charts.htm<\/a><\/p>\n

\u00a9 2019 Dr. David W. Silversides<\/p><\/blockquote>\n

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[vc_row][vc_column][vc_column_text] Cat Genetics 1.0: The Basics Cat owners, cat breeders and veterinarians with cat practices should all have a basic understanding of cat genetics. \u00a0Intuitively it is quite simple, and it\u2019s all about two.\u00a0 Two parents, but you already know that. \u00a0Two copies of every gene.\u00a0 Two copies of every chromosome. The number to remember…<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"footnotes":""},"class_list":["post-4156","page","type-page","status-publish","hentry","description-off"],"acf":[],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/labgenvet.ca\/en\/wp-json\/wp\/v2\/pages\/4156","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/labgenvet.ca\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/labgenvet.ca\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/labgenvet.ca\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/labgenvet.ca\/en\/wp-json\/wp\/v2\/comments?post=4156"}],"version-history":[{"count":8,"href":"https:\/\/labgenvet.ca\/en\/wp-json\/wp\/v2\/pages\/4156\/revisions"}],"predecessor-version":[{"id":22049,"href":"https:\/\/labgenvet.ca\/en\/wp-json\/wp\/v2\/pages\/4156\/revisions\/22049"}],"wp:attachment":[{"href":"https:\/\/labgenvet.ca\/en\/wp-json\/wp\/v2\/media?parent=4156"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}