Kehidupan tidak hanya dihuni oleh populasi manusia yang sama persis dari nenek moyang Homo sapiens hingga saat ini. Sejak Allah menciptakan gen awal di spesies manusia modern, selalu ada kegiatan pemilahan alami dalam tubuh yang menyeleksi gen-gen dalam lokus kromosom. Hal ini dikarenakan antar manusia yang berpasangan mengadakan siklus seksual yang menyebabkan adanya persilangan materi genetik dari ayah dan ibu. Bahkan Allah juga memang sudah menggariskan firmannya dalam kitab suci bahwa manusia diciptakan dari jenis manusia berbangsa-bangsa dan bersuku-suku agar saling mengenal. Sungguh karunia yang sangat besar dari adanya semua itu yang dalam biologi dikenal dengan genetika.
Allah berfirman dalam Alquran Surat Al-Hujurat ayat 13 sebagai berikut
يٰٓاَيُّهَا النَّاسُ اِنَّا خَلَقْنٰكُمْ مِّنْ ذَكَرٍ وَّاُنْثٰى وَجَعَلْنٰكُمْ شُعُوْبًا وَّقَبَاۤىِٕلَ لِتَعَارَفُوْا ۚ اِنَّ اَكْرَمَكُمْ عِنْدَ اللّٰهِ اَتْقٰىكُمْ ۗاِنَّ اللّٰهَ عَلِيْمٌ خَبِيْرٌ
Artinya: “Wahai manusia, sesungguhnya Kami telah menciptakan kamu dari seorang laki-laki dan perempuan. Kemudian, Kami menjadikan kamu berbangsa-bangsa dan bersuku-suku agar kamu saling mengenal. Sesungguhnya yang paling mulia di antara kamu di sisi Allah adalah orang yang paling bertakwa. Sesungguhnya Allah Maha Mengetahui lagi Mahateliti,” (Q.S. Al-Hujurat [49]: 13).
Pada tahun 1953, Francis Crick dan James Watson menemukan struktur heliks ganda DNA. Teori genetika atau pewarisan sifat sudah ada lebih dahulu, namun bentuk molekul ditemukan belakangan. Pada mulanya penelitian genetika diawali oleh Gregor Johan Mendel dari hasil percobannya menyilangkan tanaman ercis (Pisum sativum) dari kebun belakang gereja. Mendel melakukan percobaannya atas hipotesis Aristoteles.

Sumber: Plantlet.org
Genetika adalah ilmu yang membahas tentang pewarisan sifat dari individu kepada keturunan dengan pola khusus yang mendasari penurunan sifat tersebut. Ada pengertian secara klasik bahwa dalam genetika terdapat hukum segregasi dan random assortment yang dihasilkan dari penelitian Mendel. Dengan demikian, hukum Mendel merupakan dasar utama mempelajari genetika keturunan dengan perbandingan fenotip atau genotip berdasarkan pola hereditas. Sementara genetika saat ini sudah dikolaborasikan dengan genetika molekuler yang mengungkap adanya gen dalam segmen DNA yang dalam nukleotidanya membawa informasi genetik tertentu.
Gamet dihasilkan dari proses meiosis yaitu salah satu jenis pembelahan sel pada makhluk hidup. Pewarisan sifat pada manusia ditentukan dalam proses fertilisasi yakni pada waktu terjadinya meiosis. Meiosis berbeda dari mitosis yang hanya terjadi sekali dalam satu siklus. Meiosis terdiri dari dua tahapan yakni meiosis I dan meiosis II. Pada meiosis I inilah tahapan yang paling penting penentu sifat manusia berupa peristiwa sinapsis dan pindah silang.
Perwujudan terjadinya pindah silang adalah terbentuknya kiasma yang menjadi palang persilangan antar kromosom homolog sebelum memisah. Sebelum terjadinya peristiwa pindah silang, kromosom homolog telah melakukan penggandaan yakni masing-masing memiliki kromosom saudara yang nantinya masing-masing kromosom homolog akan memisah sewaktu anafase I. Sementara kromosom saudara akan memisah sewaktu anafase II.

Sumber: Plantlet.org
Lalu bagaimana kromosom itu bisa mempengaruhi perbedaan genetik setiap manusia? Di dalam kromosom terdapat DNA yang menjadi unit dasar pembawa sifat pada manusia karena di dalamnya terdapat gen. Di dalam gen tersebut mengkode alel-alel yang berbeda untuk sifat yang berbeda pula. Adanya alel-alel ini, dalam sebuah persilangan atau perkawinan individu seolah ada pengacakan kode-kode penentu sifat manusia sehingga akan timbul variasi dan keanekaragaman yang berbeda. Variasi genetik pada keturunan disebabkan oleh beberapa faktor yaitu pemilahan bebas pada kromosom, pindah silang, dan fertilisasi acak. Selain itu juga disebabkan oleh adanya mutasi, migrasi atau rekombinasi DNA.
Variasi gen pada kromosom dikenal dengan istilah alel. Misalnya gen tinggi TT untuk gen dominan dan gen rendah tt untuk gen resesif. Keturunan akan menjadi Tt yang menunjukkan tubuh tinggi tetapi membawa gen pendek. Pada perkawinan berikutnya jika gen Tt dengan Tt akan menghasilkan keturunan 25% TT (tinggi), 50% Tt (tinggi), dan 25% tt (pendek). Contoh ini baru untuk yang dua alel yang berbeda. Bagaimana dengan manusia yang memiliki banyak gen misalnya ada tinggi, rendah, kulit putih, kulit gelap, hidung mancung, hidung pesek, dan masih banyak lagi. Alel yang ada jika diacak dari satu persatu tentunya akan menjadi manusia dengan karakteristik yang berbeda. Makanya ada orang Arab dengan hidung mancung dan berpostur tinggi sementara orang Asia Tenggara yang berpostur kecil dan hidung pesek.
Pemilahan Bebas Kromosom
Proses ini terjadi saat proses meiosis I pada tahap metafase. Kromosom berjajar di satu lempeng yang sama. Setiap kromosom pada manusia selalu berpasangan yang disebut dengan kromosom homolog atau kembaran. Katakan jika ada kromosom A dan B, masing-masing memiliki kromosom homolog yaitu A1 dan A2, B1 dan B2. Keempat ini memiliki kombinasi A1 berpasangan dengan B1, A1 dengan B2, A2 dengan B1, dan A2 dengan B2 sehingga total ada 4 kombinasi. Gamet pada manusia berjumlah 23 yang bersifat haploid (setengah dari total kromosom manusia yaitu ½ 46= 23). Manusia memiliki kombinasi gamet dari ayah dan ibu sehingga total kombinasi menjadi 2 pangkat 23 yang berjumlah sekitar 8,4 juta. Hal ini yang mendasari perbedaan karakteristik manusia dari jumlah kombinasi 8,4 juta.
Pindah silang
Akibat adanya pemilahan bebas kromosom, kombinasi gen yang diwarisi dari orang tua sangat beraneka ragam sehingga bisa dipastikan tidak ada orang yang sama persis. Peristiwa pindah silang akan dihasilkan kromosom rekombinan yaitu kromosom individu mengandung gen orang tua. Peristiwa pindah silang terjadi pada tahap profase I pada meiosis I yaitu saat kromosom homolog saling berpasangan longgar. Di antara dua kromosom homolog dihubungkan dengan kiasma, dan di sinilah terjadinya pindah silang.
Fertilisasi acak
Peristiwa penyatuan gamet jantan dan betina menjadi zigot yang diploid (46 kromosom) ada sekitar 70 triliun. Jika dikombinasikan dengan proses pindah silang dan pemilahan bebas pada kromosom maka jumlahnya akan sangat besar. Bahkan jumlah populasi manusia saat ini tercatat 8 miliar jiwa terakhir Juli 2022 (Kompas.com). Jika ditotal dari awal manusia pertama di bumi mungkin tidak sampai 70 miliar. Jadi benar-benar semua manusia diciptakan dengan berbeda-beda.
Jika manusia diciptakan dengan kesamaan atau bahkan kloning salah satu teknik dalam bioteknologi maka akan susah mengenali satu demi satu manusia. Adanya perbedaan itulah bisa dibedakan sehingga bisa dihafalkan ciri-cirinya agar saling mengenal sesuai dengan surat Al-Hujurat di atas.
Demikian, ilmu genetika dengan dasar persilangan Mendel sampai genetika molekuler yang membuka mata di banyak bidang sehingga permasalahan seperti penyakit, pengobatan, dan sosial bisa teratasi. Genetika bukan sekadar teori yang diajarkan di bangku sekolah tapi benar-benar ada dengan bukti yang sudah sangat jelas kebermanfaatannya dalam banyak dimensi kehidupan.
Sungguh, Allah menciptakan manusia yang sangat kompleks dengan pengaturan molekuler yang terorganisir sebagai bagian dari ilmu genetika. Genetika juga merupakan bukti kuasa Allah kepada manusia sebagai insan terbaik diantara semua organisme lain di muka bumi sehingga dengan adanya perbedaan dan variasi itulah manusia bisa saling kenal mengenal.
Dengan adanya syariat pernikahan maka proses pewarisan sifat akan terus berlanjut dengan banyak kombinasi karakteristik yang berbeda-beda. Ayat tersebut menambahkan bahwa ketakwaan setiap hamba itu yang menentukan kemuliaan seseorang. Jadi dalam hal ini, perbedaan suku, bangsa, ataupun ras bukan hal yang menunjukkan kemuliaan seseorang.
Penulis : Arina Zulfa
Referensi:
Campbell, Neil.A, J. B. Reece. Dkk. (2008) Biologi Edisi Kedelapan. Jakarta: Erlangga
https://quran.kemenag.go.id/surah/49
https://plantlet.org/linkage-and-recombination-part-1-chromosomal-theory-linkage-crossing-over/
test
Membuat taman bunga ialah impian setiap pecinta alam dan keanggunan. Taman bunga adalah tempat di mana ke eksotikan alam berkumpul dalam orkestra yang mempesona. Dengan aneka macam jenis bunga yang mekar dengan beragam warna dan aroma, taman bunga menjadi surga kecil yang mengundang mata dan hati untuk terpesona. Dalam taman bunga, kita dapat menikmati paduan sempurna antara warna-warni bunga, hijaunya daun, dan kesegaran alam yang membawa kedamaian dan kegembiraan. Taman bunga adalah tempat di mana kita bisa melepaskan diri dari hiruk-pikuk dunia dan membiarkan diri kita tenggelam dalam keindahan yang tak tergantikan.
Dapatkan keindahan yang memesona dan ketenangan yang menenangkan dengan mempercayakan koleksi Ikan Koi impian Anda kepada kami. Nikmati keajaiban beraneka warna dan gerakan gemerlap koi yang anggun dalam kolam Anda, menghadirkan keindahan alami ke dalam kehidupan Anda sehari-hari. Dengan keahlian kami dan perawatan yang teliti, kami menjaga ikan koi Anda dalam kondisi terbaik, sehingga Anda bisa menikmati harmoni yang tak tergantikan dari kehadiran koi di lingkungan Anda. Percayakan kepada kami untuk menghadirkan keindahan ikan koi yang menakjubkan ke dalam kehidupan Anda.
I likewise think therefore, perfectly pent post! .
I think this web site holds some rattling excellent info for everyone :D. “Believe those who are seeking the truth doubt those who find it.” by Andre Gide.
Thanks for your posting. One other thing is that if you are disposing your property all on your own, one of the problems you need to be cognizant of upfront is just how to deal with house inspection reviews. As a FSBO retailer, the key about successfully moving your property and also saving money about real estate agent profits is awareness. The more you recognize, the easier your property sales effort are going to be. One area that this is particularly important is reports.
Awesome blog! Do you have any helpful hints for aspiring writers? I’m planning to start my own site soon but I’m a little lost on everything. Would you suggest starting with a free platform like WordPress or go for a paid option? There are so many choices out there that I’m completely overwhelmed .. Any suggestions? Thanks!
This is very interesting, You’re a very skilled blogger. I have joined your rss feed and look forward to seeking more of your wonderful post. Also, I have shared your site in my social networks!
Hello there, simply became aware of your weblog thru Google, and found that it’s truly informative. I am going to watch out for brussels. I?ll be grateful when you continue this in future. A lot of other people will probably be benefited from your writing. Cheers!
I enjoyed this! Helpful to read, but I am not sure where to start. Which of your articles would you recommend I read next?
Hey there! Do you know if they make any plugins to help with Search Engine Optimization? I’m trying to get my blog to rank for some targeted keywords but I’m not seeing very good gains. If you know of any please share. Cheers!
Wonderful blog! I found it while searching on Yahoo News. Do you have any tips on how to get listed in Yahoo News? I’ve been trying for a while but I never seem to get there! Many thanks
I’m not that much of a online reader to be honest but your sites really nice, keep it up! I’ll go ahead and bookmark your site to come back later on. All the best
hey there and thank you for your information ? I have certainly picked up something new from right here. I did however expertise some technical points using this website, since I experienced to reload the site a lot of times previous to I could get it to load properly. I had been wondering if your web hosting is OK? Not that I am complaining, but slow loading instances times will sometimes affect your placement in google and can damage your high quality score if advertising and marketing with Adwords. Anyway I am adding this RSS to my email and can look out for much more of your respective interesting content. Make sure you update this again very soon..
I like the helpful information you provide in your articles. I?ll bookmark your blog and check again here frequently. I am quite sure I will learn many new stuff right here! Best of luck for the next!
After examine a couple of of the weblog posts in your website now, and I truly like your method of blogging. I bookmarked it to my bookmark web site listing and can be checking back soon. Pls take a look at my web page as properly and let me know what you think.
whoah this weblog is wonderful i like reading your posts. Stay up the great work! You realize, many individuals are looking around for this information, you could aid them greatly.
Does your blog have a contact page? I’m having a tough time locating it but, I’d like to send you an email. I’ve got some suggestions for your blog you might be interested in hearing. Either way, great website and I look forward to seeing it develop over time.
Helpful info. Lucky me I found your site by accident, and I’m surprised why this twist of fate did not took place earlier! I bookmarked it.
Thank you, I have just been searching for information approximately this topic for a long time and yours is the best I’ve discovered till now. But, what concerning the bottom line? Are you sure in regards to the source?
One thing I have actually noticed is the fact there are plenty of common myths regarding the banking companies intentions while talking about foreclosures. One fairy tale in particular is always that the bank wants your house. Your banker wants your hard earned dollars, not your house. They want the amount of money they loaned you together with interest. Avoiding the bank will still only draw any foreclosed conclusion. Thanks for your posting.
Hmm, it seems like your site ate my first comment (it was extremely long) so I guess I’ll just sum it up what I had written and say, I’m thoroughly enjoying your blog. I as well am an aspiring blog writer, but I’m still new to the whole thing. Do you have any recommendations for newbie blog writers? I’d appreciate it.
I liked up to you’ll obtain carried out proper here. The sketch is attractive, your authored subject matter stylish. nevertheless, you command get got an nervousness over that you would like be delivering the following. unwell unquestionably come further formerly once more since precisely the similar just about a lot often inside case you shield this hike.
Hiya, I’m really glad I’ve found this information. Nowadays bloggers publish just about gossips and web and this is actually frustrating. A good blog with exciting content, that is what I need. Thank you for keeping this web-site, I will be visiting it. Do you do newsletters? Can not find it.
Write more, thats all I have to say. Literally, it seems as though you relied on the video to make your point. You clearly know what youre talking about, why waste your intelligence on just posting videos to your weblog when you could be giving us something informative to read?
I have really learned some new things through the blog post. Also a thing to I have noticed is that generally, FSBO sellers are going to reject you. Remember, they will prefer to never use your companies. But if an individual maintain a comfortable, professional romance, offering help and being in contact for around four to five weeks, you will usually be capable of win a conversation. From there, a house listing follows. Thanks a lot
I?d need to verify with you here. Which is not one thing I usually do! I take pleasure in reading a publish that may make folks think. Also, thanks for permitting me to comment!
Thanks for a marvelous posting! I quite enjoyed reading it, you can be a great author.I will make certain to bookmark your blog and will come back sometime soon. I want to encourage you continue your great job, have a nice afternoon!
wonderful issues altogether, you simply won a logo new reader. What may you suggest about your post that you just made a few days ago? Any certain?
Wonderful blog! I found it while surfing around on Yahoo News. Do you have any tips on how to get listed in Yahoo News? I’ve been trying for a while but I never seem to get there! Appreciate it
Music started playing anytime I opened this web page, so annoying!
Thanks for your fascinating article. One other problem is that mesothelioma cancer is generally attributable to the inhalation of dust from mesothelioma, which is a positivelly dangerous material. It really is commonly observed among individuals in the construction industry that have long experience of asbestos. It is caused by living in asbestos insulated buildings for long periods of time, Genetics plays a crucial role, and some persons are more vulnerable to the risk when compared with others.
[url=http://ivermectin.download/]ivermectin 250ml[/url]
[url=http://wellbutrin.monster/]wellbutrin xl generic[/url]
Simply a smiling visitor here to share the love (:, btw outstanding style and design.
Good post made here. One thing I would like to say is the fact most professional domains consider the Bachelors Degree like thejust like the entry level standard for an online diploma. Though Associate Certifications are a great way to begin, completing the Bachelors uncovers many opportunities to various employment goodies, there are numerous internet Bachelor Course Programs available through institutions like The University of Phoenix, Intercontinental University Online and Kaplan. Another issue is that many brick and mortar institutions present Online versions of their qualifications but usually for a significantly higher fee than the organizations that specialize in online college diploma plans.
Great post. I used to be checking continuously this weblog and I’m impressed! Very useful information specifically the final part 🙂 I handle such info much. I was looking for this particular information for a very long time. Thank you and good luck.
[url=https://antabuse.today/]antabuse price uk[/url]
I have been absent for some time, but now I remember why I used to love this blog. Thank you, I will try and check back more often. How frequently you update your site?
I beloved as much as you will obtain performed proper here. The cartoon is tasteful, your authored material stylish. however, you command get bought an shakiness over that you want be turning in the following. sick surely come further earlier once more since precisely the similar nearly very steadily inside case you shield this increase.
Yet another thing is that while searching for a good on-line electronics retail outlet, look for web shops that are continuously updated, trying to keep up-to-date with the hottest products, the most effective deals, in addition to helpful information on services. This will ensure you are dealing with a shop that stays over the competition and gives you what you should need to make educated, well-informed electronics expenditures. Thanks for the crucial tips I’ve learned from the blog.
[url=http://prednisolone.monster/]prednisolone pack[/url]
Thanks for your article. I would also like to say that a health insurance brokerage service also works well with the benefit of the actual coordinators of your group insurance cover. The health broker is given a listing of benefits searched for by an individual or a group coordinator. Exactly what a broker may is hunt for individuals or perhaps coordinators which often best complement those requirements. Then he presents his recommendations and if the two of you agree, the broker formulates a legal contract between the two parties.
[url=http://antibioticsop.com/vantin.html]vantin price[/url]
[url=https://pharmgf.com/clomid.html]clomid 50 mg[/url]
I have read several just right stuff here. Definitely price bookmarking for revisiting. I surprise how so much effort you place to make this type of excellent informative website.
[url=https://finasteride.science/proscar.html]buy proscar 1mg[/url]
[url=https://pharmgf.com/diflucan.html]buy fluconazol without prescription[/url]
I?m impressed, I need to say. Really hardly ever do I encounter a weblog that?s each educative and entertaining, and let me tell you, you may have hit the nail on the head. Your thought is outstanding; the difficulty is one thing that not sufficient individuals are speaking intelligently about. I am very blissful that I stumbled throughout this in my search for something regarding this.
Have you ever thought about creating an ebook or guest authoring on other blogs? I have a blog centered on the same topics you discuss and would really like to have you share some stories/information. I know my subscribers would appreciate your work. If you’re even remotely interested, feel free to send me an e mail.
Hi, I think your site might be having browser compatibility issues. When I look at your website in Chrome, it looks fine but when opening in Internet Explorer, it has some overlapping. I just wanted to give you a quick heads up! Other then that, great blog!
I am typically to running a blog and i actually respect your content. The article has actually peaks my interest. I am going to bookmark your web site and hold checking for brand new information.
[url=http://happyfamilycanadianpharmacy.online/]canadian pharmacy in canada[/url]
Penis, This is a good website Penis
Genitalia, This is a good website Genitalia
XXX, This is a good website XXX
Sex pill, This is a good website Sex pill
Steamy, This is a good website Steamy
Libido, This is a good website Libido
viagra, This is a good website viagra
Enhancer, This is a good website Enhancer
Suggestive, This is a good website Suggestive
[url=https://antabuse.party/]cost price antabuse[/url]
What an eye-opening and thoroughly-researched article! The author’s attention to detail and capability to present intricate ideas in a digestible manner is truly admirable. I’m thoroughly enthralled by the scope of knowledge showcased in this piece. Thank you, author, for sharing your knowledge with us. This article has been a real game-changer!
https://meronotice.com/informative-notice-about-coronavirus/
[url=https://tadacip.download/]tadacip 5[/url]
you’ve gotten an important weblog here! would you prefer to make some invite posts on my blog?
Today, I went to the beach front with my children. I found a sea shell and gave it to my 4 year old daughter and said “You can hear the ocean if you put this to your ear.” She placed the shell to her ear and screamed. There was a hermit crab inside and it pinched her ear. She never wants to go back! LoL I know this is entirely off topic but I had to tell someone!