Ikigai Daily
WonderGenetics fact1,776 of 1,961

Random X-chromosome inactivation early in development creates cell-line mosaics, helping produce the orange-and-black patches of most tortoiseshell cats.

A chromosome painted in fur

BiologyScienceEvolution

Why it matters

The idea in context

In cells with two X chromosomes, one is largely silenced so gene dosage does not double. The choice happens cell by cell and is inherited by descendant cells, turning the body into a patchwork of lineages. On a tortoiseshell coat, an invisible developmental decision becomes visible at a glance: genetics rendered as geography.

Türkçe

Aynı kart, başka bir dilde.

Gelişimin başındaki rastgele X kromozomu etkisizleşmesi hücre soylarından oluşan bir mozaik yaratır; çoğu alacalı kedinin turuncu-siyah lekelerine katkıda bulunur.
Tüylerde boyanmış kromozom

İki X kromozomlu hücrelerde gen dozu ikiye katlanmasın diye X'lerden biri büyük ölçüde susturulur. Seçim hücre hücre yapılır ve yavru hücrelere aktarılır; beden farklı soyların yamalı haritasına dönüşür. Alacalı kürkte görünmez bir gelişim kararı tek bakışta görünür olur: coğrafyaya dönüşmüş genetik.

Source trail

Read beyond the card.

Background reading: X-inactivationAttribution and context are revised when stronger evidence appears. Corrections are welcome through the editorial page.
Open in the iPhone appEditorial method

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