Biotechnology and its Applications (Biotechnology aur uske Applications): Class 12 Biology Chapter 10 Hinglish mein

India ke ek aam hafte ke teen scenes socho. Maharashtra ka ek cotton farmer apne khet mein apne pita ke muqable bahut kam spray karta hai. Type 1 diabetes wali ek school ki ladki lunch se pehle insulin inject karti hai. Ek laboratory ek aise sample mein viral infection report karti hai jo patient ko zara sa bhi fever hone se pehle liya gaya tha. Har scene chupchaap biotechnology par tika hai.

Industrial sense mein biotechnology (जैव प्रौद्योगिकी) ka matlab hai living cells, ya unse nikale gaye molecules, ka use karke bade scale par useful products banana. Microbes, plants aur animals, jinmein se kai engineered hain, aaj polluted soil aur sewage saaf karne, biofuels banane, food aur detergents ke liye enzymes banane, aur vaccines, medicines, test kits aur behtar crops dene mein madad karte hain.

Kisi discovery ko lab ki bench se market tak le jaane ke liye teen problems ek ke baad ek solve karni padti hain (Fig. 10.1). Pehla, sabse accha catalyst dhoondho ya banao: ek living catalyst (aam taur par selection ya engineering se improve kiya gaya microbe) ya ek isolated enzyme. Doosra, woh conditions engineer karo jinmein woh catalyst sabse tez kaam kare; yeh bioreactor ka kaam hai. Teesra, product ko recover aur purify karo jab tak woh bechne, khaane ya inject karne layak saaf na ho jaaye; yeh hai downstream processing.

Yeh chapter in tools ke peeche-peeche laboratory se bahar jaata hai: kheton mein (Section 10.1), hospitals aur clinics mein (Section 10.2), research aur medicine ke liye banaye gaye animals mein (Section 10.3), aur aakhir mein un debates mein ki living cheezon ko kaun badal sakta hai aur unka maalik kaun ho sakta hai (Section 10.4).

10.1 Agriculture mein Biotechnology ke Applications

India ko 1.4 billion se zyada logon ka pet lagbhag utni hi kheti ki zameen se bharna hai jitni woh 1970s mein jotta tha. Mote taur par us zameen se zyada food nikaalne ke teen tareeke hain, aur har ek ki apni keemat hai.

1960s aur 1970s ki Green Revolution ne pehla raasta liya. Wheat aur rice ki high-yielding dwarf varieties ko irrigation, fertilisers aur pesticides ke saath joda gaya, aur tab se India ki foodgrain harvest lagbhag chaar guna badh gayi hai. Lekin ab yeh badhat dheemi pad gayi hai. Agrochemicals itne mehenge hain ki kai chhote farmers afford nahi kar paate, zyada use karne par woh soil aur paani ko nuksaan pahunchate hain, aur conventional breeding dheemi hai aur sirf wahi traits add kar sakti hai jo un plants mein hain jinhe crop ke saath cross kiya ja sake. Biotechnology ne aur raaste khole, jinki shuruaat tissue ke chhote tukdon se poore plants ugaane se hui.

Tissue culture aur micropropagation

Ek leaf se ek disc kaato, use sterilise karo, ek band flask mein nutrients ki jelly par rakho, aur sahi hormones ke saath woh roots, shoots aur flowers wala naya plant ban sakta hai. Shuruaati tukde ko explant kehte hain aur is technique ko tissue culture (ऊतक संवर्धन). Botanists ne yeh 1950s mein samjha; jaise 1958 mein F. C. Steward ne carrot-root cells ke chhote clusters se poore carrot plants ugaaye. Yeh totipotency ki wajah se kaam karta hai.

Culture medium gel mein jama hua ek complete diet hai. Band vessel mein carbon dioxide kam aati hai, isliye explant photosynthesis se kaafi food nahi bana paata aur use ek carbon source chahiye, aam taur par sucrose. Inorganic salts nitrogen, phosphorus, potassium aur trace elements dete hain; vitamins aur amino acids metabolism ko support karte hain; agar mixture ko jelly mein jama deta hai. Asli faisla karne wale ingredients growth regulators hain, ek auxin aur ek cytokinin. Inka ratio development ko disha deta hai: balance hone par aksar callus banta hai (dividing cells ka ek unorganised lump), zyada cytokinin shoots ko badhava deta hai aur zyada auxin roots ko.

Agar bante hue shoots ko kaat kar baar-baar fresh medium mein le jaaya jaaye, to ek hi explant kuch mahino mein hazaaron plantlets de sakta hai. Yeh hai micropropagation (सूक्ष्मप्रवर्धन). Kyunki har plantlet parent se sirf mitosis se banta hai, sab mein parent jaise hi genes hote hain; aise plants ko somaclones kehte hain. Isliye ek grower ek shaandaar plant ko bina genes ki us uthal-puthal ke multiply kar sakta hai jo seeds laate hain. (Kabhi-kabhi culture process khud chhote genetic changes kar deta hai, jise somaclonal variation kehte hain, isliye growers apne stocks check karte hain.)

India mein banana iska ek zabardast example hai: Grand Naine variety ke tissue-culture plantlets bade scale par lagaye jaate hain kyunki woh uniform, healthy hote hain aur ek saath harvest ke liye taiyaar hote hain. Tomato, apple, potato, sugarcane, orchids aur kai forest trees bhi commercially micropropagate kiye jaate hain.

Meristems se virus-free plants

Cuttings, tubers ya suckers se ugaayi gayi crops mein viruses ek ziddi problem hain, kyunki har naye plant ko parent ka infection virasat mein milta hai. Phir bhi buri tarah infected plant mein bhi shoot tip par dividing cells ka chhota sa dome (apical meristem) aur leaf axils ke buds (axillary meristems) aam taur par virus se free hote hain. Viruses zyadatar plant ke vascular tissue se hokar chalte hain, jo meristem ke andar abhi bana nahi hota, aur meristem ke cells itni tezi se divide hote hain ki virus unmein phail nahi paata.

Isse growers ko bachne ka raasta milta hai (Fig. 10.3). Microscope ke neeche ek technician millimetre ke ek chhote se hisse jitna lamba meristem nikaalta hai aur use culture medium par ugaata hai; jo plant banta hai woh shuru se saaf hota hai. Potato seed-tuber programmes, sugarcane nurseries aur banana producers sab meristem culture use karte hain, aur phir healthy plants ko multiply karne ke liye micropropagation.

Somatic hybridisation

Breeders aam taur par do plants ko cross-pollination se jodte hain, jo sirf kareebi relatives ke beech kaam karta hai. Tissue culture is rukawat se bachne ka raasta deta hai. Cellulase aur pectinase jaise enzymes cell walls ko digest kar dete hain, aur peeche naked protoplasts (जीवद्रव्यक) bachte hain jo sirf apni plasma membranes se ghire hote hain. Beech mein walls na hone se do alag plants ke protoplasts ko fuse karaya ja sakta hai, polyethylene glycol (PEG) jaise chemical ya ek chhote electric pulse se.

Fused cell mein dono parents ka genetic material hota hai. Culture mein woh apni wall dobara banata hai, divide hota hai aur ek plant mein regenerate ho sakta hai jise somatic hybrid kehte hain; is process ko somatic hybridisation kehte hain (Fig. 10.4). Sabse mashhoor koshish mein tomato aur potato ke protoplasts fuse karke pomato banaya gaya. Woh uga, lekin usne kabhi tomatoes ki acchi fasal aur potatoes ki acchi fasal ek saath nahi di, isliye uska koi commercial use nahi hua. Somatic hybrids wild relatives se potato jaisi crops mein disease resistance laane mein zyada successful rahe hain.

Genetically modified crops

Kya genes ka hamara gyaan farmers ko kam chemicals use karke zyada fasal lene mein madad kar sakta hai? Tissue culture poore genomes ko copy ya combine karta hai; genetic engineering zyada precise hai aur sirf ek ya kuch chune hue genes ko move karti hai. Jin plants, animals, bacteria ya fungi ke genes is tarah badle gaye hain, woh genetically modified organisms hain (GMOs, आनुवंशिकतः रूपांतरित जीव).

GM crops aisi problems solve karne ke liye design kiye gaye hain jinse normal breeding jujhti rahi:

• Built-in pest protection, taaki farmers kam insecticide spray karein.
• Abiotic stress mein survival: drought, thand, garmi ya namkeen soil.
• Behtar nutrition: golden rice β-carotene banata hai, jise hamara body vitamin A mein badal deta hai.
• Fertiliser ka kifayati use: jo plants nitrogen ya phosphorus zyada efficiently lete hain, woh soil ko kam khaali karte hain.
• Lambi shelf life: jo fruit dheere naram hone ke liye engineer kiya gaya hai, woh transport aur storage jhel leta hai, isliye kam food barbaad hota hai.
• Factories ke roop mein plants: aisi crops jo industrial starches, biofuels, ya vaccines aur doosri drugs dene ke liye engineer ki gayi hain.

Do applications dikhate hain ki aisi crops kaise banti hain: plants jo apna insecticide khud banate hain, aur plants jo ek parasite ke genes ko silence kar dete hain.

Bt cotton

Bacillus thuringiensis (short mein Bt) ek soil bacterium hai. Jab yeh spores banata hai, to kuch proteins ko microscopic crystals mein bhi pack karta hai jo kuch insects ke liye zehreele hote hain. Farmers, organic farmers bhi, dashakon se Bt ko biological pesticide ki tarah spray karte aaye hain. Genetic engineering ek kadam aage gayi: bacterium se ek toxin gene isolate karke crop plants mein insert kiya gaya, jo ab apni leaves, stems aur bolls mein khud insecticidal protein banate hain. Bt cotton, Bt maize (corn) aur Bt soybean bade paimane par ugaaye jaate hain; rice, potato, tomato aur brinjal ke Bt versions bhi banaye gaye hain, aur Bangladesh ke farmers Bt brinjal ugaate hain.

Har strain ka toxin insects ke ek chhote group par kaam karta hai. Cotton mein target moths ke caterpillars hain, yaani lepidopterans (bollworms, budworms, armyworms). Doosre Bt strains beetle larvae (coleopterans) ya flies aur mosquitoes ke larvae (dipterans) ke liye jaanleva hain. Zyadatar doosre animals, insaan bhi, par iska asar nahi hota.

Jawaab yeh hai ki toxin ek inactive protoxin ke roop mein store hota hai. Bt leaf chabaane wala caterpillar crystals nigal leta hai. Uska midgut bahut alkaline hota hai (kai caterpillars mein lagbhag pH 10), jo crystals ko ghol deta hai, aur uske apne gut enzymes protoxin ko kaat kar active toxin bana dete hain. Active toxin midgut ki lining wale epithelial cells par specific receptor proteins se bind hota hai aur unki membranes mein ghuskar pores bana deta hai. Paani aur ions tezi se andar aate hain, cells phool kar phat jaate hain (lyse), gut wall toot jaati hai, aur insect khaana band kar deta hai aur kuch dino mein mar jaata hai (Fig. 10.5). Hamara stomach acidic hai aur hamare gut cells mein woh receptors nahi hote, isliye protein bas digest ho jaata hai.

Bt toxins ko Cry proteins kehte hain (crystal se), aur unhe encode karne wale genes cry genes hain. Saikdon jaane jaate hain, har ek insects ke ek khaas group ke against active, isliye engineers woh gene chunte hain jo crop aur uske main pest se match kare (Table 10.1). Tumhari textbook naam roman numerals mein likhti hai, jaise cryIAc; aaj ki naming arabic numerals use karti hai, cry1Ac. Dono ka matlab same gene hai.

India ne cry1Ac wale apne pehle Bt cotton hybrids 2002 mein approve kiye. Do genes, cry1Ac aur cry2Ab, wali second generation 2006 mein aayi, taaki pest ko ek saath do toxins ka resistance develop karna pade. Aaj India ke cotton area ke nau-dasve hisse se zyada mein Bt hybrids boye jaate hain, aur Bt cotton abhi bhi desh mein commercially ugaayi jaane wali akeli GM crop hai.

Bt crops ki ek kamzori hai: evolution. Pink bollworm, jo cotton boll ke andar chhup kar khaata hai, India ke bade hisse mein dono toxins ke liye resistant ho gaya hai, aur farmers ko uske against phir se spray karna pada hai. Resistance sabse tezi se tab phailta hai jab district ke har plant mein toxin ho, kyunki tab sirf resistant moths hi bach kar mate karte hain. Isliye growers se non-Bt cotton ka ek refuge rakhne ko kaha jaata hai, jo aaj aksar seed packet mein mile non-Bt seeds ke roop mein aata hai, taaki susceptible moths bachein aur rare resistant moths ke saath mate karein (Fig. 10.6).

Pest-resistant plants: RNA interference

Har pest insect nahi hota. Nematodes naam ke chhote roundworms soil ke neeche se crops par hamla karte hain. Sabse nuksaandayak mein se ek hai root-knot nematode, Meloidogyne incognita. Iske larvae tobacco aur kai doosri crops ki roots mein ghus kar root cells ko feeding sites bana dete hain; roots phool kar knots (galls) ban jaati hain, paani aur minerals shoots tak pahunchna band ho jaate hain, aur harvest ka bada hissa barbaad ho jaata hai.

Is baar hathiyaar khud eukaryotic cells se udhaar liya gaya. RNA interference (RNAi) mein ek double-stranded RNA (dsRNA) har us gene ko switch off kar deta hai jiske messenger RNA ka sequence usse match karta hai. Nature mein aisa dsRNA kahan se aata hai? Kai viruses ka genetic material RNA hota hai aur multiply hote waqt woh dsRNA banate hain, aur kuch transposons (‘jumping genes’) RNA ke zariye apni copy banate hain. Healthy cells mein lamba dsRNA kam hi hota hai, isliye yeh danger signal ka kaam karta hai, aur RNAi cell ko matching messages nasht karne deta hai.

Cell ke andar Dicer naam ka enzyme dsRNA ko lagbhag 21–23 nucleotides lambe chhote tukdon mein kaat deta hai, jinhe small interfering RNAs (siRNAs) kehte hain. RISC naam ka ek protein complex har tukde ka ek strand guide ki tarah rakhta hai, complementary sequence wala koi bhi mRNA dhoondhta hai, aur use kaat deta hai ya uska translation block kar deta hai. Gene abhi bhi maujood hai, lekin uska message kabhi protein nahi banta.

Plan yeh tha ki tobacco plant khud trigger banaye. Researchers ne aise genes chune jinke bina nematode zinda nahi reh sakta, aur Agrobacterium ko vector bana kar tobacco ko nematode sequence ki aisi copy di jise plant dono directions mein transcribe kare, jisse sense RNA aur complementary antisense RNA bane. Dono strands plant ke cells ke andar pair hokar dsRNA ban gaye (Fig. 10.7). Jab nematode ne roots khaayi to usne yeh dsRNA le liya, uski apni RNAi machinery ne matching mRNA ko silence kar diya, aur parasite zinda nahi reh saka. In transgenic plants ki roots un galls se kaafi had tak free rahin jo normal plants ki roots par chhaye the.

10.2 Medicine mein Biotechnology ke Applications

Recombinant DNA technology se pehle kai protein medicines animal organs ya donate kiye gaye human blood se nikaalni padti thin. Supply limited thi, batches alag-alag hote the, ek foreign protein immune system ko bhadka sakta tha, aur donor material mein chhupe infections ho sakte the. Engineered cells ne yeh badal diya. Woh kisi bhi size ke fermenters mein human proteins banate hain, jo hamare apne proteins jaise identical hain, aur kyunki body in proteins ko apna pehchanti hai, allergic aur immune reactions rare ho jaate hain aur koi donor infection andar nahi aa sakta.

Tumhari textbook duniya bhar mein approve hue lagbhag 30 recombinant therapeutics ki baat karti hai; aaj yeh ginti kai sau tak pahunch gayi hai. India inmein se kai banata hai, jinmein low-cost biosimilars bhi hain, aur 1997 mein Hyderabad ki ek company ne hepatitis B ke against India ki pehli desi recombinant vaccine launch ki. Kuch examples Table 10.2 mein list kiye gaye hain.

10.2.1 Genetically Engineered Insulin

Insulin, pancreas ke beta cells ka ek hormone, body cells ko blood se glucose lene deta hai. Type 1 diabetes wale log lagbhag bilkul insulin nahi banate aur unhe roz insulin chahiye; lambe samay se type 2 diabetes wale kai logon ko bhi iski zaroorat padti hai. 2023 mein publish hui ek ICMR study ke andaaze se lagbhag 101 million Indians ko diabetes hai, isliye demand bahut badi hai.

1921 mein discovery ke baad lagbhag saath saal tak diabetes wale log abattoirs se ikattha kiye gaye pigs aur cattle ke pancreas glands se purify kiye gaye insulin par nirbhar the. Animal hormone isliye kaam karta hai kyunki woh lagbhag same molecule hai: pig insulin hamare insulin se 51 mein se ek amino acid par alag hai, aur cattle insulin teen par. Lekin kuch patients ne ise foreign protein maan kar react kiya, allergies ya antibodies ke saath, aur supply meat trade par depend karti thi. Human insulin banane wala bacterium dono problems solve kar deta: zyada insulin chahiye, to bas zyada bacteria ugaao.

Mature insulin ek chhota protein hai: 21 amino acids ki chain A aur 30 ki chain B, jo do disulphide bridges (–S–S–) se judi hain, aur chain A ke andar ek teesra bridge hai. Lekin pancreas do chains alag-alag nahi banata. Woh ek chain banata hai, proinsulin, ek pro-hormone jo processing ke baad hi active hota hai (pepsinogen se compare karo, jo tabhi active pepsin banta hai jab uska ek hissa kaat diya jaaye). Proinsulin mein ek connecting hissa, C peptide, chain B ke end ko chain A ki shuruaat se jodta hai. Chain fold hoti hai, bridges bante hain, aur phir enzymes C peptide ko kaat kar nikaal dete hain, jisse mature insulin release hota hai (Fig. 10.8).

Bacteria yeh processing nahi kar sakte, aur recombinant DNA technology se insulin banane mein yahi sabse badi rukawat thi. Iska hal, jo American company Eli Lilly ne Genentech mein develop kiye gaye methods se apnaya, yeh tha ki do chains alag-alag bacterial cultures mein banayi jaayein aur baad mein jodi jaayein. Har chain ke liye ek chhota synthetic gene banaya gaya, aur har gene apne alag E. coli plasmid mein gaya, isliye bacteria ke ek batch ne A chains banayi aur doosre ne B chains. Purification ke baad chains ko aisi conditions mein milaya gaya jinmein sahi disulphide bridges bante hain, aur result tha human insulin (Fig. 10.9). 1982 mein USA mein approve hokar aur 1983 se bazaar mein aakar, yeh recombinant DNA technology se bani pehli medicine thi.

Product ka amino acid sequence bilkul natural hormone jaisa hai. Baad ke processes microbes mein khud proinsulin banate hain aur factory mein enzymes se C peptide kaat dete hain. Kai manufacturers, jinmein se kai India mein hain, ab E. coli ya yeast mein insulin banate hain, saath hi insulin analogues bhi jinmein ek ya do amino acids jaan-boojh kar badle jaate hain taaki insulin tez kaam kare ya zyada der tak chale.

10.2.2 Gene Therapy

Inherited diseases ki zyadatar medicines faulty gene ke effects ka ilaaj karti hain, jaise woh protein inject karke jo patient nahi bana sakta. Gene therapy (जीन चिकित्सा) jad par vaar karti hai: missing product baar-baar dene ki jagah, woh use banane ke instructions deti hai. Gene ki ek working copy patient ke cells mein pahunchayi jaati hai, jahan woh woh kaam karti hai jo faulty copy nahi kar paati.

Aam delivery vehicles disabled viruses hote hain. Viruses naturally apne genes ko un cells mein le jaate hain jinhe woh infect karte hain; vector mein disease paida karne wale genes hata diye jaate hain aur unki jagah therapeutic gene aa jaata hai.

Pehli approved clinical gene therapy 1990 mein USA mein hui. Patient, jo tab chaar saal ki thi, ko adenosine deaminase (ADA) deficiency thi. ADA ek enzyme hai jo deoxyadenosine ko saaf karta hai, jo DNA breakdown ka by-product hai. Iske bina by-product jama hota jaata hai aur developing lymphocytes ko maar deta hai, isliye immune system mushkil se kaam karta hai aur bachcha ek ke baad ek infection se beemar padta hai; yeh condition severe combined immunodeficiency (SCID) ka ek form hai. Yeh dono parents se mile faulty ya missing ADA gene ki wajah se hoti hai.

ADA deficiency wale bachchon ko working enzyme ke regular injections (enzyme replacement therapy) se zinda rakha ja sakta hai, lekin yeh sirf kuch had tak madad karte hain aur zindagi bhar chalne chahiye. Bone marrow transplant disease ko cure kar sakta hai, lekin sirf tab jab acchi tarah match karne wala donor mile, aur kai bachchon ke paas koi nahi hota.

1990 ki team ne body ke bahar kaam kiya (Fig. 10.10). Ladki ke blood se lymphocytes alag karke culture mein multiply kiye gaye; ek disabled retrovirus se unmein working ADA gene, cDNA ke roop mein, insert kiya gaya; aur engineered cells ko dheere-dheere wapas uske bloodstream mein daala gaya, jahan unhone ADA banaya. Lekin mature lymphocytes hamesha divide nahi hote rehte, isliye unki ginti ghat gayi aur har kuch mahine mein naye infusions ki zaroorat padti thi.

Lambe samay ke cure ke liye gene un cells mein hona chahiye jo naye lymphocytes banate rehte hain. Tumhari textbook batati hai ki early embryonic stage par cells mein gene daalna permanent ho sakta hai. Lekin embryo ko badalne se woh eggs ya sperm bhi badal jaate hain jo woh baad mein banayega, isliye change aane wali generations tak jaayega. Aisi germline gene therapy India ki gene therapy ki national guidelines (ICMR, 2019) ke tahat allowed nahi hai aur zyadatar deshon mein banned ya sakhti se restricted hai. Asal mein jo raasta use hota hai woh hai bone marrow ke patient ke apne blood banane wale stem cells: ek baar theek karne par woh healthy lymphocytes banate rehte hain. ADA deficiency ke liye is tarah ka treatment 2016 mein Europe mein approve hua.

10.2.3 Molecular Diagnosis

Socho ek aisa virus jo fever laane mein do hafte leta hai. Un do hafton mein patient theek mehsoos karta hai, doosron ko infect kar sakta hai, aur use treatment se pehle hi fayda mil sakta tha. Jo tests disease ke effects dhoondhte hain (serum ya urine mein changes) ya jinhe bahut saare microbes chahiye (microscope slide, culture), woh aam taur par tabhi positive aate hain jab pathogen multiply ho chuka ho aur symptoms dikhne lagein. Molecular methods seedhe pathogen ke apne molecules, uske DNA, RNA ya proteins, dhoondhte hain, aur unhe tab bhi pakad sakte hain jab woh bahut kam hon. Teen tools sabse important hain: recombinant DNA probes, polymerase chain reaction (PCR) aur ELISA (Table 10.3).

PCR yeh problem copy karke solve karta hai. Har cycle target sequence ko zyada se zyada double kar sakta hai (RNA virus ko pehle reverse transcriptase DNA mein copy karta hai). Das cycles use lagbhag hazaar guna kar dete hain ($2^{10}$ = 1024 hai), aur tees cycles lagbhag ek billion guna. Isliye mutthi bhar copies bhi itni ho jaati hain ki detector unhe dekh sake, symptoms aane se bahut pehle (Fig. 10.11).

PCR ka use infants mein HIV infection confirm karne aur patients mein virus ki maatra track karne, tuberculosis aur uske drug resistance ka pata lagane mein hota hai, aur COVID-19 pandemic ke dauraan yeh SARS-CoV-2 ka standard test tha. Tuberculosis ke liye India ke apne chip-based PCR test, Truenat, ko 2020 mein World Health Organization ne endorse kiya. PCR cancer cells mein aur sickle-cell anaemia aur thalassaemia jaise inherited disorders ke peeche ke genes mein mutations bhi dhoondhta hai.

Probe DNA ya RNA ka ek chhota single strand hai jis par ek label hota hai, pehle ek radioactive atom aur aaj aksar ek fluorescent dye. Yeh sirf us DNA se chipakta (hybridise hota) hai jiske bases iske apne bases ke complementary hon. Cloned cells ke ek set ko test karne ke liye unka DNA ek membrane par fix kiya jaata hai, probe us par se bahaya jaata hai aur jo probe bind nahi hua use dho diya jaata hai. Jahan bhi probe ne pair kiya, wahan X-ray film par (autoradiography) ya scanner mein ek spot dikhta hai. Jis clone ka gene probe wale region mein mutated hai, woh probe se pair nahi kar sakta aur koi spot nahi deta (Fig. 10.12).

ELISA (enzyme-linked immunosorbent assay) nucleic acids ki jagah proteins ke saath kaam karta hai. Iska key ingredient ek antibody hai jo sirf ek target ko pehchanta hai aur kisi ko nahi. Disease ke hisaab se test ya to microbe ke apne molecules, uske antigens (proteins ya glycoproteins), pakadne ke liye design hota hai, jo dikhate hain ki woh abhi maujood hai, ya un antibodies ko jo patient ne uske against banaye hain, jo dikhate hain ki immune system ka usse saamna ho chuka hai.

Ek common form, 'sandwich' ELISA, mein ek plastic well par antigen pakadne wale antibodies ki coating hoti hai. Phir enzyme se juda ek doosra antibody kisi bhi pakde gaye antigen se bind hota hai. Jab ek colourless substrate daala jaata hai, to enzyme use coloured product mein badal deta hai; rang jitna gehra, antigen utna zyada (Fig. 10.13). ELISA ka use donate kiye gaye blood ko HIV aur hepatitis B ke liye screen karne aur fever ke pehle dino mein dengue virus ka NS1 antigen pakadne mein hota hai.

10.3 Transgenic Animals

Jo mouse blue light mein hara chamakta hai kyunki usmein jellyfish ka gene hai, woh ek transgenic animal (पारजीनी जंतु) hai: kisi doosre source ka gene uske DNA mein jod diya gaya hai aur wahan kaam kar raha hai. Saare transgenic animals mein 95 per cent se zyada mice hain, kyunki woh chhote hain, unhe rakhna sasta hai, woh har kuch hafton mein breed karte hain aur unke genes bahut acchi tarah samjhe gaye hain. Fish, pigs, cows, sheep, goats, rabbits aur rats ko bhi transgenic banaya gaya hai.

Ek common method mein chune gaye gene ki copies, jo ek aise promoter se judi hoti hain jo use sahi tissue mein on kare, ek fertilised egg mein inject ki jaati hain. Embryos ek foster mother mein rakhe jaate hain, aur bachchon ko test karke woh dhoondhe jaate hain jinhone gene le liya hai (Fig. 10.14). CRISPR–Cas9 jaise genome-editing tools ab aise changes zyada precisely karte hain.

Itni mehnat kyun? Paanch reasons khaas hain (Table 10.4).

Biological-products wale raaste ko kabhi-kabhi 'pharming' kehte hain. Jo proteins itne complex hain ki bacteria unhe sahi se nahi bana sakte, unhe animal ko nuksaan pahunchaye bina uske doodh se ikattha kiya ja sakta hai, aur aise hi kaam ka lakshya phenylketonuria (PKU) aur cystic fibrosis ke treatments bhi rahe hain. Disease models bhi utne hi important hain: jo mouse human bimari develop karta hai, uski madad se researchers kisi bhi insaan par aazmaane se pehle treatment test kar sakte hain.

10.4 Ethical Issues

Genes ko dobara likhne ki taakat aise sawaal uthati hai jinhe akele science suljha nahi sakta. Kya research ke liye kisi animal ko bimari dena sahi hai? Kya bacterium ka gene hamare khaane mein pahunchna chahiye? Fayda kise hota hai, aur risk kaun uthata hai? Aise sawaal laboratory mein nahi, balki ethics aur law se suljhaaye jaate hain: living cheezon ke saath kya kiya ja sakta hai iske agreed standards, aur unhe laagu karne wali official bodies.

Saavdhaani ke biological reasons bhi hain. Kheton mein chhoda gaya GM organism ek ecosystem ka hissa ban jaata hai, jiske effects ka andaaza lagana mushkil hai: uske genes pollen ke zariye wild relatives tak ja sakte hain, toxin target ke alawa doosre insects ko nuksaan pahuncha sakta hai, pests mein resistance evolve ho sakta hai (jaise pink bollworm mein hua), aur khaane mein naye protein ko allergy ke liye check karna zaroori hai. Isliye har release ko case-by-case parkha jaata hai.

India mein GM research aur release Environment (Protection) Act, 1986 ke tahat 1989 mein banaye gaye rules se chalte hain. Kaam ek laboratory mein shuru hota hai jiski nigrani uski Institutional Biosafety Committee (IBSC) karti hai. Department of Biotechnology ke under Review Committee on Genetic Manipulation (RCGM) research aur chhote, confined field trials ko review karti hai. Ministry of Environment, Forest and Climate Change ke under Genetic Engineering Appraisal Committee (GEAC) bade field trials aur GM organisms aur products ko environment mein release karne ka appraisal karti hai, aur final faisla government leti hai (Fig. 10.15). Tumhari textbook committee ka purana naam use karti hai, Genetic Engineering Approval Committee; iska naam 2010 mein badla gaya.

Isi system se bilkul alag nateeje nikle hain. Bt cotton 2002 mein approve hua. Bt brinjal ko 2009 mein GEAC ne clear kiya, lekin 2010 mein government ne uske release par moratorium laga diya, jo abhi tak hata nahi hai. GM mustard ke environmental release ke liye GEAC ki 2022 ki approval ko Supreme Court mein challenge kiya gaya. 2022 se, jin plants ko bina koi foreign DNA insert kiye genome-edit kiya gaya hai, unhe GMO rules se chhoot hai, aur 2025 mein India ne apni pehli do genome-edited rice varieties release ki.

Patents aur biopiracy

Sawaalon ka doosra set ownership ke baare mein hai. Patent government dwara ek limited period ke liye diya gaya right hai, India mein 20 saal, jo inventor ko doosron ko bina permission invention banane, use karne ya bechne se rokne deta hai. Patent paane ke liye invention naya ho, usmein inventive step ho aur woh useful ho. Kai deshon mein engineered microbes, genes aur processes patent kiye ja sakte hain. Mushkil tab shuru hoti hai jab koi aise plant, nuskhe ya crop variety ko patent kar le jise farmers ya tribal communities ne bahut pehle khoja aur sudhaara tha, jaise ki woh naya ho.

Basmati dikhata hai ki aisa jhagda kaise aage badhta hai. Yeh khushbudaar long-grain rice India aur Pakistan ke Indo-Gangetic plains ke farmers ki peedhiyon ki mehnat hai, ek aisa region jahan Earth par rice ki sabse zyada diversity mein se kuch hai. 1997 mein Texas ki ek company, RiceTec, ne un rice lines ka US patent le liya jo usne Basmati ko semi-dwarf rice se cross karke breed ki thin. Iske kuch claims itne broad shabdon mein the ki woh khud Basmati jaise rice tak pahunch jaate, jisse Indian farmers aur exporters chinta mein pad gaye. India ne 2000 mein patent ko challenge kiya, aur 2001 tak zyadatar claims wapas le liye gaye ya reject ho gaye, aur sirf teen specific rice lines protected rahin. Tab se India ne ek tay region ke rice ke liye Basmati ko geographical indication (GI) ke roop mein register kiya hai.

Doosre patents ne traditional Indian nuskhon ko nishana banaya. Zakhm bharne ke liye turmeric ke use par 1995 mein diya gaya ek US patent 1997 mein revoke kar diya gaya, jab India ki Council of Scientific and Industrial Research (CSIR) ne purane Sanskrit texts aur 1953 ke ek journal article se dikhaya ki yeh use bahut pehle se jaana jaata tha. Neem oil ke antifungal extract par 1994 mein diya gaya ek European patent 2000 mein revoke hua. Aise challenges aasaan banane ke liye India ne Traditional Knowledge Digital Library (TKDL) banayi, jo Ayurveda, Unani, Siddha aur yoga ke purane texts ko aise records mein badalti hai jinhe duniya mein kahin bhi patent examiners search kar sakte hain.

Yeh itna important kyun hai? Duniya ki biodiversity ka map dekho: India, Brazil aur Indonesia jaise tropical deshon mein zyadatar species hain, jabki zyadatar biotechnology companies aur research ka paisa North America, Europe aur Japan mein hai. Kisi vaidya ka yeh gyaan ki ek khaas patta khoon rokta hai, ek taiyaar clue hai, aur jo company use follow karti hai woh saalon ki andhi screening se bach jaati hai. Insaaf yeh maangta hai ki jis community ke gyaan se khoj shuru hui, use uski kamaai mein hissa mile (dono raaste compare karo).

Deshon ne laws banakar jawaab diya hai. India ne apna Patents Act 2002 mein (woh second amendment jiska zikr tumhari textbook karti hai) aur phir 2005 mein amend kiya: traditional knowledge ko invention ke roop mein patent nahi kiya ja sakta, aur applicants ko use kiye gaye kisi bhi biological material ka source aur geographical origin batana zaroori hai. Biological Diversity Act, 2002 (2023 mein amend hua) ke tahat Indian bio-resources ke foreign users, aur unke aadhaar par patent chahne wale kisi bhi insaan ko National Biodiversity Authority ki approval leni hoti hai, aur faydon ko un communities ke saath share karna hota hai jo unhe conserve karti hain. International level par Convention on Biological Diversity (1992) aur uska Nagoya Protocol (2010) access with benefit sharing ka yahi principle tay karte hain.