AMASO

Kubijyanye na Wikipedia
A close up of a blue-green human iris

Ibara ryijisho ni fenotipiki ya polygeneque igenwa nibintu bibiri bitandukanye: pigmentation ya iris yijisho ryijisho [1] [2] hamwe ninshuro-biterwa no gukwirakwiza umucyo ukoresheje uburyo bwa turbid muri troma ya iris . [3] Mu bantu, pigmentation ya iris iratandukanye kuva mwijimye wijimye ugahinduka umukara, bitewe nubunini bwa melanin muri epitelium ya iris pigment (iherereye inyuma ya iris), ibirimo melanin biri muri stroma (iri imbere yimbere iris), hamwe n'ubucucike bwa selile ya troma. [4] Kugaragara kwamaso yubururu, icyatsi, na hazel biva muri Tyndall ikwirakwiza urumuri muri troma, ibintu bisa nkibibara ubururu bwikirere bwitwa Rayleigh gutatanya . [5] Ntabwo ibara ry'ubururu cyangwa icyatsi kiboneka muri iris ya muntu cyangwa amazi ya ocular . [6] [7] Ibara ryijisho rero ni urugero rwibara ryimiterere kandi riratandukanye bitewe nuburyo bwo kumurika, cyane cyane kumaso yamabara yoroshye .Amaso afite amabara meza yubwoko bwinshi bwinyoni aturuka ku kuba hari izindi pigment, nka pteridine, purine, na karotenoide . [8] Abantu nandi matungo bifite fenotipiki itandukanye muburyo bwamaso.[9]

Genetic[hindura | hindura inkomoko]

Molekile ya Pteridine.

Ibara ryijisho ni umurage warazwe na gene zirenze imwe. [10] [11] Izi genes zishakishwa hifashishijwe amashyirahamwe kugirango ahindure mato mato ubwayo no muri genes zituranye. Izi mpinduka zizwi nka polymorphism imwe-nucleotide imwe cyangwa SNPs. Umubare nyawo wa gen ugira uruhare mu ibara ryamaso nturamenyekana, ariko hari abakandida bake. Ubushakashatsi bwakorewe i Rotterdam (2009) bwerekanye ko bishoboka guhanura ibara ryamaso hamwe n’ibice birenga 90% byukuri byijimye nubururu ukoresheje SNP esheshatu gusa. [12] Hariho ibimenyetso byerekana ko genes zigera kuri 16 zishobora kuba nyirabayazana w'amaso y'abantu; icyakora, genes ebyiri nyamukuru zijyanye no guhinduranya amabara y'amaso ni OCA2 na HERC2, kandi byombi biherereye muri Chromosome 15 . [13]

Guhindura ibara ryamaso[hindura | hindura inkomoko]

Ijanisha ryamaso yoroheje muburayi no hafi yuburayi nkuko umuhanga mubya antropropologue Peter Frost abivuga.

Abana benshi bavutse bafite ibisekuruza byabanyaburayi bafite amaso yibara. Mugihe umwana akura, melanocytes (selile ziboneka mumatwi yumuntu wumuntu, kimwe nuruhu numusatsi) bitangira kubyara melanine . Kuberako melanocyte selile ikomeza kubyara pigment, mubitekerezo ibara ryamaso rirashobora guhinduka. Ibara ry'amaso akuze rishyirwaho hagati y'amezi 3 na 6 y'amavuko, nubwo ibi bishobora nyuma. [14] Kurebera iris yumwana kuva kuruhande ukoresheje urumuri rwanduye gusa ntirugaragaze inyuma ya iris, birashoboka kumenya ahari melanine nkeya cyangwa idahari. Iris igaragara ubururu muri ubu buryo bwo kwitegereza birashoboka cyane kuguma ubururu uko uruhinja rusaza. Iris igaragara nka zahabu irimo melanine ndetse no muri iyi myaka mike kandi birashoboka ko izahinduka ubururu igahinduka icyatsi cyangwa icyatsi nkuko uruhinja rusaza

Referances[hindura | hindura inkomoko]

  1. https://doi.org/10.1111%2Fj.1600-0749.2005.00268.x
  2. https://doi.org/10.1006%2Fexer.1998.0518
  3. https://books.google.com/books?id=c2xyxwlm2UkC&pg=PA9
  4. https://en.wikipedia.org/wiki/CiteSeerX_(identifier)
  5. Sturm R.A. & Larsson M., Genetics of human iris colour and patterns, Pigment Cell Melanoma Res, 22:544-562, 2009.
  6. https://doi.org/10.1109%2FICCV.2005.215
  7. https://doi.org/10.1021%2Fj150239a007
  8. https://en.wikipedia.org/wiki/Carotenoid
  9. Morris, PJ. "Phenotypes and Genotypes for human eye colors." Athro Limited website. Retrieved 10 May 2006.
  10. https://web.archive.org/web/20060909190624/http://www.biosci.ohio-state.edu/~pfuerst/courses/eeobmg640/reading1eyecolor.pdf
  11. https://pubmed.ncbi.nlm.nih.gov/12573082
  12. https://pubmed.ncbi.nlm.nih.gov/12573082
  13. https://doi.org/10.1038%2Fjhg.2010.126
  14. Burroughs, A. and Leifer, G. (2001) Maternity Nursing: An Introductory Text, W.B. Saunders Medical, p. 172